The Ultimate Edelbrock Carburetor Tuning Guide

[@Compcams1976]

Great video! Very informative!

[@65Bogie]

I always thought my car ran pretty good and then I stumbled upon this video and realize that my vacuum advance was on the wrong port, what a difference thank you very much.

[@MuscleCarSolutions]

Nice! Glad it helped. Tuning is a process. Keep working the process and it’s always amazing how good an old carburetor will run.

[@skipthompson288]

This is by far the best explanation I've seen on how to adjust an eddy carb. Thank you!!!

[@teddybertgarage4119]

You bet, very useful, thanks for chairing 👍🏻

[@Squares.SSs.and.Bowties]

Super helpful video! You made absolute sense out of the jet and needle chart which confused me until I saw your video. THANK YOU!!

[@dukebacher1216]

Sir, First off, thank you for taking the time to help others... We appreciate you sharing your knowledge and experience. I have a 1992 Dodge D250 pickup w/360 (LA, not magnum) engine. It originally came with TBI, and ran pretty well until one day Pfffft. No power to coil or EFI. Literally replaced everything including the computer twice, still nothing. I purchased one of the Jegs HEI distributors (to fit a Dodge), an Edelbrock Performer intake, and at first a Holley 1460 Carb. Holly just pumped gas into the cylinders, and it chugged. Never could make it run right... I am using the stock in-tank fuel pump, going through a filter, a bypass regulator (5psi) , another filter, and then one of those "dial-style" deadhead regulators (just to be sure) before the carb. A buddy gave me a Carter/Edelbrock 9635S 4bbl, (600cfm) which I promptly put a kit into, and the truck is extremely happy. I did have to remove the vacuum advance off the dist. because it would hit the intake or the firewall. I "locked down" the timing slider inside the dist, but it still has centrifugal advance intact. With the Eddy/Carter carb, I can get a really nice idle, but it's a little too low (little under 500 RPM). If I attempt to raise it, it suddenly starts sputtering like it's running on about 4-5 cyl. Same thing happens if you lightly rest your foot on the gas pedal. just a little more throttle, and it's back to smooth, and accelerates quickly. Likewise if slowing down, slight pedal pressure (or being between 550-850 RPM) causes this sputtering miss, then it gets down into the idle circuit and smoothes out, but at really low RPM's. The engine is bone stock, with 160,000 miles, Automatic trans, and runs like a scared rabbit with the Edelbrock 4bbl, except for that blasted stutter just above idle. If I could just get it to idle up a little more and to stop that stuttering, It would be running perfect. Am I going to have to find a way to re-install the vacuum advance, or is there something that I am missing? Going down the highway, it purrs... and is 3-4 times more responsive now, than it ever was when it was TBI. Gonna need to do some mods to get my speedometer and overdrive to work again, as they were controlled by the ECU, but that sputtering drives me nuts! Thoughts?

[@dukebacher1216]

@@MuscleCarSolutions Yes, I did use an Edelbrock kit on it. Strange thing, last night I was going to visit a friend in a rural area... when I got onto his road (straight and flat) I put all 270 foot pounds into the pedal and let 'er howl up to about 80-ish MPH (according to phone app) and it now idles at about 750-800 and no sputter! I will have to figure out a way to make the vacuum advance fit in the limited space I have. I figured the mechanical advance would be ok, but if the vacuum will make a difference... I'll massage the firewall a bit.

[@dukebacher1216]

Latest update: truck still runs perfect, and am getting 12mpg (used to get 8...) now! I've decided I'm not touching a thing on it. (except to add an overdrive enable switch)

[@MuscleCarSolutions]

Nice! Well glad it’s running well. Keep those filters clean and you’ll get lots of good miles on it!

[@ianfurqueron5850]

Thanks for a video. I have a Triumph TR8 with an Edelbrock carb (replacing the OEM cross-ram dual Zenith Strombergs). My carb experience is with other British cars with SU and Zenith Strombergs, and despite dreaming of muscle cars in my youth, this is my first car with an American style 4 bbl. I have been struggling with the car since I bought it last year. I came with no choke installed (manual linkage on the carb, but no cable installed), so cold starts have been a SOB. Once it does start, it runs pretty good, although it run super-lean during cruising. The previous owner installed a AFR gauge which is show the rating well in the 16:1 range (or higher) at speed. The temp gauge will also creep up almost to the point of over-heating. Oddly enough, in stop and go traffic with the engine idling, it richens up (13:1 or so) and the temp gauge is perfectly normal. While watching the video, I paused it and went to look at the vacuum ports. Passenger side - capped. Driver side - open (with the vacuum hose to the distributor disconnected. The large center port - also open. Rear port - plugged (the power brakes are connected to a port on the manifold). Something tells me that completely open center port would represent a large vacuum leak? I know from my years fiddling with SUs and Z-Ss, vacuum leaks are the bane of carburetors. I swapped the distributor line to the passenger side port, moved the small cap and capped the large port. I bought a tuning kit, but now I'm wondering if I really needed it... unfortunately, my interior is apart (fixing more previous owner "mods"), so it'll be a day or so before I can start the car and see if the capped ports makes a difference. I wonder if a phenolic plate between the carb and the manifold might help, but unfortunately the space under the hood of a TR8 is tight.

[@MuscleCarSolutions]

You’ve made the right choices and corrected some horrible issues with the vacuum leak in that PCV port up front! Yes, you absolutely need the tuning kit. You have a great advantage there with the AFR to help you tune once you get ready. Yes a block for the heat transfer is important. There is a link in the video description of the narrowest spacer that Edelbrock makes. If you can use it, anything helps!

[@ianfurqueron5850]

Thanks, I'll take a look at the spacer. I also need to check the timing and advance are correct. It's funny - a common saying from working on old British (and Swedish) cars is "90% of carburetor problems are ignition related." Especially since many of these cars are still running points distributors.

[@MuscleCarSolutions]

@@ianfurqueron5850 that’s a statement that proves itself true over and over again! Good luck, and if you run into any issues don’t hesitate to let me know. Always happy to help if I can.

[@tomnekuda3818]

The AFB is the easiest carb to tune I've ever had in terms of an American carb. With their Strip Kit and the charts it is super simple. The only carb I've ever found that is easier to dial in are Webers. I had 42DCOE side drafts on a Chevy I had and, with beer in hand, I found them to be super.

[@bobjackson4171]

Fantastic! Well explained, at a 5th grader level. I wish other folks making vids like this were such good teachers.

[@MuscleCarSolutions]

@@bobjackson4171 well I mean I wasn’t trying to act like anyone watching is a fifth grader. 😂 But I’m glad you liked the video. I’ve got TONS more on Edelbrock carburetors. 👍

[@bobjackson4171]

@@MuscleCarSolutions Lol! Maybe you are more intuitive when making your vids. If the goal is sharing knowledge, then you certainly “get it” sir. I liked, but did forgot to subscribe. I will go do so now! : ) I plan to watch your other vids as well. Thanks for expanding my knowledge and capabilities that will come from it!

[@MuscleCarSolutions]

@@bobjackson4171 that was the whole reason why I started uploading videos. I get a ton of satisfaction when I can help folks. Don’t hesitate to ask any questions along the way. Always happy to help if I can.

[@bobjackson4171]

@@MuscleCarSolutions Thank you! I might take you up on your offer as I go. Thanks in advance!

[@happysailor9858]

Man...THANKS!!!! You have delivered a super informative well filmed session again. I've the way you explain these things.

[@cbobmonster]

Dude, you are freaking amazing and knowledgeable. Great video I sent you a common earlier about stumbling and backfiring on acceleration and it just started happening Dodge 318.

[@trifivegarage8683]

Thanks this video has some very good info. I found lowering the fuel pressure to 3lbs. Helped the hot restart issue as well. Doesn't seem to creep as far up after shut down. The ethanol fuel is causing a lot of problems. For those of us running carbs these days.

[@trifivegarage8683]

@@MuscleCarSolutions OK.. I think I will give that a try if I continue to have heat soak problems. Summer is coming and it gets pretty hot here in florida. I'm running the shorter edelbrock spacer 3/8" for the EPS manifold. I have plenty of hood clearance still. Thanks.

[@bryanroupe8646]

A 1 inch spacer should help. I run them on everything.

[@rogjackson]

Stock 1413 (800cfm) on 454 BBC mild cam street car with a T350 automatic transmission. Incoming fuel pressure is 6.5 ish. Ran perfectly for last 5 years accross all throttle positions/weather conditions. Recently, (warming in Northern CA) I get a hesitation from a standing stop to full power (iow punching off the line), but it does go for just a second before the hesitation. Then after the hesitation, everything is fine. From cruise to full throttle no problem. So it's just a hesitation from standing stop to full power, but the hesitation doesn't hit until about a second off the line. Carb looks clean generally and I've never adjusted a thing because it has worked perfectly up to now. Thoughts? Educated guess? I appreciate anyone's input. Cool video!!

[@MuscleCarSolutions]

Ah these conversations always hurt my feelings. 😂 Imagine how much better it will run when you tune it! What’s your engine vacuum at idle? Match the step up spring to it. Then you can adjust from there to remove any hesitation. What is your initial timing set to? When does fill advance come on and what is it? The pressure is on the high side. Just be aware of that if you start having issues. I’d start there and you can work through the tuning process to really get it dialed in. You’ll be surprised what you put up with as “normal” once it’s been tuned for your application.

[@denisonjesse]

I installed edelbrock wood spacer and fuel pressure regulator like the video suggested. Now my chevelle runs better. Great video !!

[@MuscleCarSolutions]

Nice! Good work!

[@mkhy3565]

Thank you. Not sure why Edelbrock stopped putting this tuning chart in the installation manual. It was frustrating just finding it on their website. Need to use a PC, not a phone. This solves alot of issues and shame on Edelbrock for removing this out of their manual. Thanks for the video

[@jondough4116]

Bought mine at summit racing and I got a bunch of Manuels 2yrsvback

[@c.pc.5805]

Sir I love the idea of 2 fuel filters this way everything is protected.

[@harvestblades]

Especially for those of us running original gas tanks on forty year old vehicles.

[@ArnCital]

There is a lack of information on A/F ratios vs power and fuel economy with regards to stressing the engine (knock, ping, burned valves). For example what is the best A/F for fuel economy while cruising without leaning out the engine too much? My truck is a 1985 F-250 HD (5,900# certified scales) with a fresh 460, T-19 4-speed, 4x4, high boy, 9:1 c.r. with forged pistons, mild cam, stock heads/exhaust. Dyno at 4,200' is 246 HP/4,200 rpm at the rear wheels (Dana 70 rear end) and max torque at 2,500 cruising rpm. Best number for fuel economy I could find was 15.4 A/F. I leaned out a 1405 to one stage leaner (at 4,000' elevation) and the truck will get up to 11 mpg and runs strong. That said, 200 miles on fresh plugs shows the porcelain insulator to be a clean white and not a light grey or brown that is optimum; the ground electrode has a slight buildup of deposits. There is NO ping or knock so I am good there. My point is that it is a good idea to read the spark plugs while tuning. I may be just slightly too lean and will experiment with rods and jets. My AutoMeter A/F shows 15.4 A/F when cruising and above to 16 with slightly more power for passing, etc. WOT power and idle is 12-13. Had I installed stainless steel or stellite-faced exhaust valves then I would not worry too much about being slightly lean. If you cannot measure it then you cannot troubleshoot it, you can only guess and I hate guessing. I am still looking for a good book or read on A/F tuning.

[@ArnCital]

@@MuscleCarSolutions Thanks for the rapid response. I have planned on lowering the A/F ratio. Nowhere on the internet or library have I found studies of varying A/F ratios and effects on driveability, engine load, engine damage, and so on. I am an industrial engineer and dealt with numbers and not opinions. That is why I monitor the A/F and vacuum along with load and rpm. Too expensive to add a gear. BTW, the engine is built as strong as I could with Eagle rods and Autotec forged pistons. It is capable of handling 550 HP and I have about 300 HP at the flywheel. Timing is 8 deg BTDC on a stock dizzy. After observing retaliative coarse A/F changes with the EDDY then I am now considering EFI because I can fine tune the engine fuel parameters.

[@garlandjones7709]

What an engine desires for a/f is not a static/constant number. Each engine will like a different number. Anyone can get you ballpark, but in the end, it's similar to timing There's not a magic rule outside of experimenting. Called "tuning"

[@wesleewilson_]

Great video! I'm reading through the manual and trying to wrap my head around how this carburetor works. Do you have a simple explanation for what components effect which driving conditions? IE: idle mixture screws determine idle afr during idle, but also; primarily jets effect this too? Then when accelerating, springs and metering rods kick in. Then, during wide open throttle, primary, secondary, and idle mixture screws determine afr. Am I correct here? Basically, I'm trying to narrow down what to change by looking at afr during different driving conditions. Also, what is a good afr for each of these stages when shooting for fuel economy?

[@coachk7674]

great stuff, I have a new 1406 Edelbrock on a 72 K1500V8, 350, 5.7 etc. manual choke cable and have recently moved from sea level to above 9200 feet. today for the first time it would not start and drained a battery trying. before I start over, my question is: does the high altitude affect the cold starts?

[@MuscleCarSolutions]

It affects every operation on a carb. Absolutely. Higher elevation means less oxygen. You’ve got some tuning to do!

[@cbobmonster]

I know this video was a long time ago, but just curious my 318 Dodge under acceleration is sputtering and backfiring once in a while and it just started doing it was wondering if you had any issues excuse me information it’s got an AVS to Edelbrock on it

[@MuscleCarSolutions]

@@cbobmonster don’t know. Could be a number of things. Verify timing and ignition components. Once an engine is under load, that’s when it puts stress on ignition system components. Bad grounds can cause this as well. That’s where I’d start. Then you can start looking at fuel. If it’s a lean condition causing it, it could be fuel filters are clogged or restricted. Fuel pump might not be able to keep up when the fuel demand increases. Garbage blocking secondary jets. Step up springs are incorrect or need a change to a different rate spring. You can also add in potential vacuum leak(s). Start working through and eliminate the possibilities until you find the issue.

[@waynep343]

put a 10 micron fuel filter before the mechanical fuel pump to keep sediment out of the fuel pump check valves.. 1984 corvette fuel filters are 10 micron.. when sediment gets in the check valves the fuel pressure held by the pump in the line to the carb is reduced. this reduction in fuel pressure allows the fuel in the line to the carb to boil.. the expanding vapor pushes liquid fuel backward thru the fuel pump.. .leaving the carb low on fuel. this reduces fuel boil over and hard to start engines because they are flooded.. when the sediment in the fuel pump gets thru to the needle and seat.. it can when the fuel level is reduces allow fuel vapor to expand and overflow the carb.. if you have an off idle stumble with an edelbrock.. cold engine count the fractions of turns to lightly seat the idle mixture screws.. take them out.. with a can of carb cleaner.. blast a 1 second spray down the idle mixture screw hole... 1 SECOND.. followed instantly by a blast of compressed air. do this 2 or 3 times for each idle mixture screw hole.. this blows sediment out of the idle feed restriction and the idle air bleed. in the primary booster assembly. if you have flat spots and you are running an engine over 360 cubic inches.. and especially over 400 cubic inches.. you may have to use a 61 to 80 drill set and one size at a time drill the idle feed restrictions in the side of the primary booster assemblies. its behind the idle air bleed on the side. you want to take the top off the carb.. then take the primary boosters out.. 2 screws. figure out what size the second part of the passage is. go up 0.001 .. reassemble and test drive .. you will need to readjust the idle mixture. the idle speed then test drive. if you get a flat spot at around 1000 or 200 above base idle.. or up to about 2200 RPMs before the primary circuits take over completely.. keep drilling 0.001 at a time. look up Low speed circuit.. look up idle transition circuit.. look up economizer circuit. edelbrock and holley removed this info from the carb manuals to allow the carb tuners something to work with. .

[@michaelnowak3570]

I am trying to cure a slight stumble off idle. Open it runs really well. Idle can be slightly rough after I adjusted mixture so that is better. Timing is on. The just off idle is not smooth into power.

[@MuscleCarSolutions]

Have you made any adjustments to the accelerator pump to verify if you need more fuel or less?

[@dbriggs1689]

Fantastic video thanks for the advice. Im starting this journey on a 75 f100 with a mild cam 460. So far ive determined its an old edelbrock 600cfm but i got ignition maintenance to get sorted out first.

[@MuscleCarSolutions]

Yup. If you get the supporting systems right first (ignition and fuel supply), tuning becomes very easy. Good luck! Don’t hesitate to ask any questions along the way. Happy to help where o can.

[@dbriggs1689]

@@MuscleCarSolutions Thank you.

[@rustyridesgarage672]

I live in Loveland Colorado whereabouts should my Jets be setted for a 600 CFM Edelbrock running into tunnel ram running into stock 350

[@crash1769]

very informative. I finally understand in plain english the tuning chart. I have had number of people explain this to me but couldn't understand it until now. thanks Muscle car solutions.

[@MuscleCarSolutions]

Good deal! I’m glad it was well received. I’ve worked on these carbs since I bought my first one in 1989. I still use that chart every single time I tune one. Extremely valuable!

[@hanger44smba78]

My truck surges when driving. I'm running a 600 4bbl edelbrock. What do you think it is. It feels like it runs strong then skips on and off running on all 8.

[@chevylandtv670]

Can someone help me out! I have a brand new avs Edlebrock 1406 on a stock 305 with a computer delete my idle n park is high but when n drive it pretty good, also my clothes smell like I been riding a dirt when I stand by the car also I’m seeing smoke come out the carb when I shut the engine off using an aluminum quadrajet spacer this is a brand new Edlebrock carburetor straight out the box any suggestions would help

[@MuscleCarSolutions]

Sounds like you’re into the transfer slots at idle which would cause the rich condition. Keep in mind the 650 is too much carburetor for a stock 305 so you’ll be fighting the rich condition for awhile.

[@davidkeeton6716]

The manual I have with my 1413 800 cfm carb says that the passenger side small port is for emissions controlled engines and the driver side port is for non emissions controlled engines/distributors. Right now I'm actually using the original 1964 point distributor. Should I use the one on the driver side, that I am using?

[@MuscleCarSolutions]

The better question would be how big is the cam profile? Is it stock? Use the timed port. Is it an aggressive long duration cam? Use the full manifold port.

[@reriley2002]

I’m running dual edelbrock Avs 500’s on a pretty stock sbc. I have a stumble right off idle if I nail the throttle. If I roll into the throttle, it burns the tires. The plugs are all nice and tan, msd, vac. Advance distributor, timing set at 10 deg. Btdc. Full advance is 36deg. By 2500 rpm. The chrome headers are turning blue, which would indicate lean to me. Where do I start? I do not have the book as I bought this whole setup used. I am assuming that both carbs. Have the stock jets, springs and rods, but I have not verified that yet. The pump shot linkage on both carbs is set in the center hole. Electric fuel pump, regulator with gauge, 2 fuel filters, and aluminum 1” carb spacers. Running 4psi of fuel pressure.

[@MuscleCarSolutions]

Lots of questions and places you can potentially start. I’d add some more initial timing to start with. It’s time to begin to look at tuning the carbs as well. I wouldn’t rely on the chrome headers being a good indication of a lean condition. In my opinion, the only way I will tune any dual set up is with an AFR. Preferably a dual O2. I know they are very expensive but it’s really the best way to tune those carbs and set timing. I know 30 years ago Dad did it all by ear but there is a wild card in all this - we have horrible fuel today with ethanol. So consider that investment if you plan on keeping that set up.

[@DeanBishop-gb9mx]

Great video, I just finished building a first gen 350. I have it in a run stand and as a project want to learn my edelbrock carb and how to make it right. I assure you that you will be hearing from me with questions. Can you tell me the best way to communicate with you. Thank you

[@MuscleCarSolutions]

Best of luck! They’re actually very easy to tune and work on. I’ve got a whole playlist of Edelbrock carburetor content. Just drop any questions in the video you’re watching. If I get the notification, I’ll respond.

[@erik9685]

I have a Carter AFB 650. It is rather new and has not been used. It has been sitting since October 23. My problem is i just installed a new small block in a 1970 chevelle. And i got the car to run. It takes about a dousen times to turn over before it fires up and runs. There is a POPING noise comming from the exhaust pipe. I believe its comming from thec passenger side pipe. Is that a carburetor issue? How do i handle this issue?Is the poping noise a symptom of the car running rich? I set the timing @ degrees and the total timing is at 32 degrees at 3500 RPM with the vacuum advanced disconnected.

[@jonjacobsen6339]

I have a Ford 302 crate motor and just installed an Edlebrock AVS2 1916 Off-road carb. I believe this motor has around 300 hp, but not exactly sure. I'm getting a stumble sometimes off idle. I have tried all 3 adjustments on the accelerator pump location & found it runs better on the leaner setting. However, I am still getting a stumble. The extent of the stumble varies from none, to somewhat significant. Where do you recommend I go from here? Thank you,

[@MuscleCarSolutions]

Ok that’s good. Now you know it needs to be leaned out. Get a calibration kit and you can start making adjustments. Step up springs first. Then you can start on the tuning chart.

[@stjp6599]

Hello, eddie carb 600 on 72 Dodge Challenger 340. Starts great cold. Idles great when kickdown.Take off get to first light when at temp,always have to give slight bump to pedal to lower idle. Thoughts?

[@MuscleCarSolutions]

Linkage adjustment? Electric choke? Not releasing? Fast idle cam sticking?

[@ciaranlowe5547]

Excellent video thank you so much for sharing your knowledge. I have one question, I’ve built a Windsor 351 60 thou over AFR heads and Edlebrook AVS2 800cfm carb and manifold. The engine is not installed yet. Is 800 cfm too big . If it is, can I adjust the carb downwards ?

[@MuscleCarSolutions]

You can’t change the CFM of a carburetor. What is the max rpm on this engine?

[@ciaranlowe5547]

@@MuscleCarSolutions street use only

[@MuscleCarSolutions]

@@ciaranlowe5547 need an rpm. What’s the cam rated for? What range? It’s important.

[@ciaranlowe5547]

@@MuscleCarSolutions 1500 to 5000 rpm range using a Lunati roller cam 112 lobe separation 108 center line rolle rockers 1.6 ratio. Cam part # 20350711. Hope this helps

[@MuscleCarSolutions]

@@ciaranlowe5547 yup. That’s exactly what you need to know. By the math, that engine would need a CFM of around 523.72. If it’s just a street cruiser with a really low rpm range, you’ll have a way easier time tuning with a 650 or 500. That 800 will be an extremely rich running engine that you won’t be able to tune away.

[@willemtheron]

If the step-up springs do not fix a hesitation, stumble etc. and you go on to change the metering rods, do I need to go back to the first spring that was in there before I started changing to different springs?

[@MuscleCarSolutions]

That’s the difficulty con tuning by just feel. An AFR would let you know if those changes were effective before you move on to working else. Keep the springs you selected, then make your rod/jet change and see if it gets better.

[@tonyvermeer7409]

I have a 1406. When adjusting the fuel regulator, do you set it for the MAX it will allow? I have mine set at 5.5 lbs. when it is at high idle. After I drive it then check it again, it drops to between 3-4.

[@MuscleCarSolutions]

I always start at 6 at idle and tune down from there as needed. I’d you’re dropping that much pressure, it’s likely one or more issues. Fuel lines too close to a heat source. You’re using a deadhead style regulator and they are famous for dropping some pressure. Put a clear filter before and after the regulator and see what the difference looks like. Once you get it sorted out, remove the filter after the regulator. We’re not a fan of one there. 😉

[@marks-yw5ij]

I'm very new to figuring out how to set up/ tune my edelbrock carb. I sont believe me secondaries are opening. When looking down the carb and going from idle to about 5500rpm I dont see them opening. Is this right? How can I fix this ?

[@armandomendoza3167]

Will this eddlebrock tuning guide work on a Rochester? I've noticed the the numbers kind of match on jets. Rods I can't remember. It has been years since I worked on a carburetor. I'm thinking of a EFI conversion to a carburetor set up.

[@JDorval319]

what discretion should I head to lean or rich? when your car hesitates and backfires when you go WOT., 383 stroker SBC, running a Edelbrock 1407,

[@MuscleCarSolutions]

@@JDorval319 head richer. Plus timing. Plus step up springs. Plus accelerator pump adjustment.

[@mrbeatty13able]

I have an edelbrock AVS2 650cfm. Which direction turning the mixture screws will do what? Ex: does turn the screws to the right lean out the mixture and left makes it rich or is the opposite true? Thank You

[@MuscleCarSolutions]

When you screw them in, you’re restricting fuel flow. Also this might be useful to you; kzbin.info/www/bejne/lXLKooeLf9drl68

[@mrbeatty13able]

@@MuscleCarSolutions Thank you

[@wayneking3408]

A question regarding AFR readings, 4106 carb in 1978 chev 350, when running down the highway @ 60 mph, my AFR is showing 14.0 -14.3, when I come to a hill it drops to 10.5 - 12.5 and the secondary has not cut in, are these numbers normal? I would like to see the up hill numbers higher to save fuel

[@MuscleCarSolutions]

@@wayneking3408 when you come to a hill you’re under load as the vacuum drops in the engine and meters more fuel. Go back to your calibration kit and follow the chart to go a little leaner. 14:1 is ok. Not optimal, but ok. Anything leaner than that you’re asking for bigger issues.

[@thedobermangang3503]

i got 1990 k5 blazer 5.7 had it rebuild with a few up grades everything is pretty mush stock i up graded the cam to a howard cam rattler lift 225/230 duration 0.50/227/235 centerline 03 i still have the factory swirl port heads i got headers 3' pipes all the way back i up graded my torque converter to 2000 to 2400 stall and 4:10 gears i just put my engine in about a week ago it was a tbi so i converted it to carb...im having problem trying to get it to run right i put a brandnew edelbrock carb 1406 on it..i got 12-887 holley regulator set it to 6 psi i got it to run starts up good but its backfiring and popping out my exhaust ..i have a vacuum port on my regulator but did not hook it up dont no if thats the problem or not..or is the carb to small for my set up...you can smell the burning and the raw gas in park when u accelerate and give it more gas it sound good but at idling its popping and backfiring like someome popping fire crackers..tell me what you think

[@rumbador]

I’m about to install a 1406 carburetor to a stock 327 engine hope don’t run into a lot of trouble. Great video will help me a lot

[@rumbador]

Definitely will take your advice about putting two filter. Thank you

[@rumbador]

Bone Head can you recommend me one in particular

[@jimmyjamesbbq]

When tuning dual quads do you tune then the same? Progressive linkage. Like if I do a metering rod change for cruise do I also use the same number rod for the second carb? 355 avs2 500’s. Running rich at cruise and real rich at WOT. Thanks.

[@MuscleCarSolutions]

You’re always going to fight a rich condition. You’re way over carbureted. So just get used to that and all the things that will come with it. Lots of oil changes, spark plug changes and a little more time tuning as conditions change. No they don’t get tuned the same. Progressive linkage is the right way to go. Generally I’ll lean the secondary carb out as far as I can. Run as much as I can off the primary, if that is how your linkage is set up. Some run off the secondary carb and the primary is only used at WOT. In which case I lean out the primary. There’s a problem with all that. You cant change CFM. You’ll still be flowing that amount of air and the air movement through the venturi is what signals the metering circuits to provide fuel. All you can do is try to lessen the fuel but the signal will continue to be there and continue to fight you.

[@rodshuffy4045]

Just wondering, I always hear make sure timing is right. Well how do I know that? Im at 7000 feet elevation and my engine will not under any circumstances run correctly at factory timing specs. So carb is rich....duh 7000 ft. Plugs black with carbon so can't read them for timing. Suggestions? Right now I'm at 22 deg BTDC at idle in N and in Park. 38 deg advanced at wot with 12 deg vac advance. Is that close enough to be "right" Im setting carb idle speed per the "square" transition slot and adjusting timing to get needed RPM at idle. Is that correct?

[@arcorob]

Great video but confused on the front vacuum ports (around 7:30 in the video) . I have a 1966 mustang, Edelbrock Performer Manifold and carb, original style vacuum advance distributor. I was under the impression that the right (drivers side) is what I should use and the left was for type that have egr. Am I wrong? I also notice with a vacuum gauge, left port is Zero unless throttle is applied whereas right port has constant vacuum. HELP ..LOL... I want it to be hooked up correctly. Thanks !!!

[@arcorob]

Bone Head yup I knew that and thanks for straightening this out. But now begs the question of vacuum gage and setting idle air fuel. I have seen you should get max vacuum when setting, then back down 1/2 turn on each side. How do I get max vacuum if it's zero at idle? Use the other side?

[@arcorob]

@@MuscleCarSolutionsYou are awesome...thanks for the quick clear replies !!!

[@Washitguy]

So, because I am dummy... which port to use when using a vacuum gauge? Driver or passenger side?

[@sed6]

@@Washitguy Driver side for running a vacuum gauge.

[@bgqtr1]

I do have a question. I have the chart, tuning kit, 5.5lbs fuel pressure. Have set float levels. Can't get it to idle. Wants to die at about 1000rpm. Was very rich but I thk Ive made some ground on that. Has a mother thumper cam. Sounds great but seems problematic. Pls advise. Tks

[@bgqtr1]

Oops sorry. It's a 1407 edlebrock

[@MuscleCarSolutions]

Those cams are a little harder to tune. What trans? Converter? What engine are you working on?

[@bubbastrahan87]

I'm trying to troubleshoot a problem with my 1406 edelbrock. At idle, the engine runs fine, and revs up fine, but when I put it in gear to drive and press the gas, it doesn't respond and lugs the engine down. It doesn't die, but I can floor the pedal and engine doesn't increase RPM. Ever heard of that issue? or think that is something else than the carb? I can't find any good information about the problem I'm having.

[@bubbastrahan87]

@@MuscleCarSolutions ended up getting another carb to try and truck runs fine now. So its narrowed down to something wrong with that carburetor internally. Haven't torn into it yet to find out the problem

[@sidecarbod1441]

10:10 The tuning chart for the 500 carb has got at least 3 errors in it! If you work out the area of a jet and then the two cross sectional areas of the rods you can work out the flow area for any given combination of jet and rod, you can then compare this to any other combination. I use an XL spreadsheet to work all of this out, it has shown that the percentage figures of change that Edelbrock quote in their chart is sometimes wrong!

[@tylerhutchinson3646]

Hey I just put my create 5.8 in with a 1406 Edelbrock. Now I know it's really set for economy. But I ordered rods and springs. Your videos have show alot. But I'm getting a feel for my next step. I thought I had it tuned pretty good but iv got this stumble in each drive and idle that I'm trying to work out.

[@MuscleCarSolutions]

Yup. Keep tuning. You’ve got the tuning kit and that’s a great start. Make some changes to the accelerator pump. I did a video on that. Adjust fuel pressure. Did a video on that as well. Keep working with your timing as you make adjustments that get you good results. You’re a little limited with the older performer series carb on the secondary side, but you still have lots of tuning points to get it dialed in. As long as the cam profile isn’t too wild, and what you’re using it for, you’re on the right track.

[@dalejrfan820002000]

I have a question about the secondary. ? Ok I how a after market throttle cable bracket. For the gas pedal and the kick down cable. Ok Trying to get it setup Wright is a pain. Because I don't think the secondary are opening. ?

[@MuscleCarSolutions]

Secondaries are vacuum operated. The throttle linkage will open Tuesday primary side and the secondaries on the bottom side of the carburetor. The top weighted valve is controlled by the load on the engine. When there is enough load and the vacuum drops, the valve will open.

[@dalejrfan820002000]

@@MuscleCarSolutions Ok so if I'm driving 55 mph and floor it should they open up? The carb IS new. I'm trying to figure this out 😂😂😂

[@MuscleCarSolutions]

Yes. Because it’s when you hit the gas, the load on the engine increases and the vacuum drops. They open.

[@dalejrfan820002000]

@@MuscleCarSolutions Ok let me ask a dum guestion how will I know when the open?

[@MuscleCarSolutions]

It’s the wrong question. The right question is how will you know if they don’t open? The engine will fall flat on its face and not engine RPM/vehicle speed.

[@craigheidelberger3325]

At high RPM or WOT she cuts out. What are the things I should look for? It has 6psi and I can blow right thru the fuel filter. Any info would be great and thanks for the video.

[@craigheidelberger3325]

@@MuscleCarSolutions O man, I left out a tad bit of info. Sbc 350 bored .060, 650 Edelbrock choke plate removed. (I live in Texas), 280 Comp cam, Weiand Stealth intake (dual plane) hooker headers, cast iron Summit racing heads. ( like a vortex according to my machinist) 700R4 tranny, 2800 stall, 4:10 posi,tires are 28" from bottom to top. HEI ignition with a "high output module". I had it dyno tuned about a year and a half ago. The (what I think) starving for fuel situation started about 3 weeks ago. Also pardon some of my ignorance I'm an automotive weekend warrior. 😆 I appreciate your time.

[@craigheidelberger3325]

@@MuscleCarSolutions truck will sit a maximum of 2 weeks at a time every now and then. I use 93 octane and to be honest I don't know what percentage of ethanol is in the gas we have here in the D/FW area. But I have not tinkered with the truck since dyno tune. I checked to make sure distributor is still tight and it is. I did notice right after the tune truck would start with no pumping of gas. Now...... After truck sits for about 2 days I have to pump gas 2 or 3 times to start it. (For about the last 3 month's or so)

[@craigheidelberger3325]

@@MuscleCarSolutions I am leaning toward ethanol contamination. I will replace the fuel filter (which is before the manual pump) and see what happens from that point. It's wet right now so it will be a day or 2 before I can get it on the road for a test. What would you consider sitting a long time? And thanks for your help once again.

[@craigheidelberger3325]

Just replaced the fuel filter and what difference. I really appreciate your advice. Its the simple things that get overlooked. I was able to blow right thru the old filter but like you said it must lose fuel pressure at wide open throttle. Now........ we need to discuss in the future about making her go faster. Any advice would be great. Looking to replace cast heads with aluminum heads just need the best bang for the buck. Unfortunately I have dished pistons and cant afford to replace lower half (pistons) right now.

[@craigheidelberger3325]

Well.......... guess what? The hesitation came back (intermittently) at wide open throttle. This weekend I'm going to blow out the line toward the gas tank with compressed air with the hopes that maybe the inlet line which has a tiny little net is slightly clogged. At the carb I'm reading 6psi but who knows at wot. If I replace the fuel pump, the only hp ones seem to be 8 psi at Summit Racing. What are the consequences of running 2 extra psi? I guess I'm automatically leaning to toward a delivery starvation issue.......

[@salmineo3931]

OK still having issues with this rebuilt 1411. I only work on the car whenever I get a chance, so it's not like it's taking this long to figure out. Anyway, I have 4 dead cylinders on my 440, 1,4,6 and 7. No change in idle on those 4 when disconnected from the dizzy cap. The plugs are sparking. My understanding is these 4 cylinders all run off the right side (facing carb) of the carb. So my issue is fuel. I blew air through the idle/mix screw holes. Strong thru the left side, not so much through the rt side. Obviously, I have a restriction. My question is, without dismantling the carb again, how can I clean out this passage and where does the passage go inside the throat of the carb? Thanks

[@MuscleCarSolutions]

Something could be blocking that passage and a full disassemble would be the route to go. Keep that compressed air handy. Once you get it apart that’s what I would use to see if you can determine where your possible blockage is.

[@hkrueger9235]

I know this is an old video but I just rebuilt my Edelbrock 1406. I took my time, cleaned everything thoroughly and put everything back exactly as it needed to be except one screw up, literally. I mixed up my jets and I'm not sure which is which now and I'm having issues with the carb flooding out big time. Would that or could that be my culprit or did I do something else wrong? This is my second carb rebuild on an Edelbrock.

[@MuscleCarSolutions]

Could very well be yes. If you go to my website there is a pdf that has the markings of the rods and jets so you can identify them. It’s in the resources section of the site. Also don’t discount the fuel system. Making sure you have the right amount of pressure to the carb is extremely critical.

[@hkrueger9235]

@@MuscleCarSolutions thank you sir for answering my question so promptly. I will definitely look into that and take care of it once I get home and off the truck this weekend. You have an excellent channel. I learn a lot from you, UTG's and David Vizard. You guys ROCK! Thanks again.

[@jamesmccoy5590]

Do you know what would cause fuel not to go to the carberator with a new edelbrock carburetor and a new fuel pump assembly

[@MuscleCarSolutions]

Difficult to say. Make sure the pump is working. Make sure your filters aren’t clogged. Do you have a vented gas tank cap?

[@barneywarwick1038]

i have a 93 dodge Dakota with the 318 it's fule injection now how can i get more horsepower out of fule injection if i switch over to carboraitor i was told go with the holly 600cfm 4bbl electric choke and the air gap intake and a return line fule pump regulator the transmission is ran by the computer can i keep the transmission

[@olliej914]

running into either a carb or vaporizing issue.. most likely both.. im running a holley fuel pressure regulator on my 302 82 mustang near the passenger firewall on my carter AFB . if the regulator gets hot and stops reading does this mean it expanded to allow max flow? or has it collapsed? getting hard to start after sitting hot. and stumbling after idling/heavy loads.

[@MuscleCarSolutions]

Check out my video on heat soak.

[@carlosbaudoin7757]

Hi I have a 8867 edelbrock carbureter on a rover 3.5 liter v8 and wont keep de idle plus when I accelerate seams like no fuell or it's run out of it . Please would you help me by the way I'm in south america tks

[@MuscleCarSolutions]

We’ll need to confirm what you have. That number isn’t a part number or a date code. My website is listed in the about section here and you can email me pictures and I’ll try to help you.

[@TheTexasDuke]

Hey so just recently inherited my fathers red 1983 gmc shortbed he’s passed sadly, so I tuned my new carb but ya keeps flooding on just giving it gas and putters out, then I have to wait 30 mins to retry and move it

[@MuscleCarSolutions]

Lots of things to look at. If it’s blowing past the needle and seats then figure out why. Get a pressure regulator and dial the pressure to 6psi or lower. Take the top off the carb and see how much garbage is on there and clean as necessary.

[@Vinventure1]

I picked up a truck with this carb on it, do you know where I can possibly download the owner's manual?

[@MuscleCarSolutions]

Yup! If you go to the Edelbrock website and put in the part number of your carb, and go to that page, there will be a link to download it.

[@PSmolchek]

GREAT VIDEO - quick question. Just dropped a crate motor in my '67 Camaro - car sat for about 6-8 months while I was working through pulling the engine apart and deciding what to do. When I put the new motor in, I didn't rebuild the carb at first until about 60 miles into the rebuild the car just didn't seem to be running right. Lagging, no strong pickup. So I pulled the carb, disassembled and did a cleanup on it, replacing the gaskets but keeping the jets. Replaced the small needles in the float assembly. Car is running but just doesn't seem to have that punch I expected - and also, after the rebuild, when I am on full throttle around 60-70 mph and I let off the throttle, it 'stays' - pedal doesn't stick, but the engine RPM's really don't drop like they should until I 'pop' the throttle and then she drops like normal. What part internally did I not check or install correctly that would be allowing that to happen? THANKS.

[@MuscleCarSolutions]

I’ll start by assuming your ignition system is in good shape and working properly. What is your total timing set at and what RPM does it go to full advance? Ok so just like the video, how is your fuel system set up? What is you’re pressure regulator set at? Where is your accelerator pump set at? Stock middle hole or did you add more fuel or leave it alone? As far as the not dropping in RPM when you let off the gas, that’s going to be a throttle return spring issue. What are you running there?

[@PSmolchek]

@@MuscleCarSolutions THANK YOU! Appreciate the quick response. To your questions: 1. Yes, ignition system working properly. Car starts and runs normally. Voltage at the coil is 11.98. 2. Timing: was set at 10deg TDC at 650 rpm per the instructions with the crate motor from GM Perf with vacuum advance off. This theoretically should produce 32deg of total advance at WOT. 3. Fuel system: I took notes. I have a single SS filter AFTER the pump. Do not have a pressure regulator. Car didn't have one and ran for three years. Assumed pressure was 'good' but now I will look at putting an inline regulator. 4. Stock middle hole on the accelerator pump. 5. Throttle spring - running the standard spring that was on the car already. Has plenty of 'pull' to it so I don't know why its not responding. When the hood is open and the engine is running, I can hit and hold the throttle and when I release it drops as normal. Seems to be on load and north of 60mph when it sticks. THANK you again for the information. I downloaded and am reading the Edelbrock manual for the 1406 today to learn more.

[@MuscleCarSolutions]

I would verify when your all in advance hits. What RPM. A common mistake is thinking that because something ran well before then the additional tuning points or support isn’t needed. For sure get a regulator and a gauge. Keep an eye on the pressure from time to time. It will change over time on a mechanical pump and you’ll need to adjust. Set the accelerator pump on the one closest to the pivot. That’s the smallest shot of fuel. See how it responds. If it’s worse, go to the furthest one to give it the biggest shot of fuel. See if it’s better or worse. I’d verify the timing first. Then adjust the accelerator pump. That’s the free stuff. But I’d get a regulator and a gauge and get it installed. Set at 6psi initially. You can adjust down lower later as you tune. Question on fuel. Running E10 I’m assuming? Not E85? Or blessed enough to use non ethanol fuel?

[@pooroledaddyfishing8132]

Great video, very helpful in understanding the chart. What should the timing be on the 454 I have, the vacuum advance is plugged at the distributor and both caps on the carb

[@pooroledaddyfishing8132]

Bone Head , I think it’s a regular gm distributor when the motor was put in they said I didn’t need the vacuum advance part. Coil pack on top of distributor. I didn’t know if I needed that to be hooked up .

[@lancestrahm2362]

Great video. I have a question. I have a 351w with a 600 cfm edelbrock carb, 1405 I believe. I rebuilt the carb and everything was going good, I'd get on it ran just fine. The 351w is rebuilt also, nothing special except gt40p heads. Well now when I drive it it runs fine but if I get on it hard it'll do a nice fish tail smoke tires or if i drive it for 10 minutes or so, then it all of a sudden runs like crap. I've noticed also when I take a turn at any stop sign or light it stutters for few seconds. Any help would be appreciated thanks.

[@MuscleCarSolutions]

Could be a number of things. What’s your fuel pressure set to? Is the carburetor bolted directly to the intake? Fuel pressure and heat soak could cause either of those issues.

[@lancestrahm2362]

@@MuscleCarSolutions Pressure is right at 6, I have a 2 inch spacer in between intake and carb. The muffler is kinda close to the electric fuel pump, think maybe the heat from the muffler could be heating the fuel up and causing it?

[@MuscleCarSolutions]

@@lancestrahm2362 what type of spacer? If its aluminum, it will transfer the heat. Yes, if the exhaust is too close to fuel lines of the pump, sure it could be cooking it.

[@lancestrahm2362]

@@MuscleCarSolutions it's a black plastic spacer

[@MuscleCarSolutions]

@@lancestrahm2362 had to ask. half the time its an aluminum spacer which is obviously an issue. You've got the good one!

[@kylerrichardson4858]

Resurrecting this masterpiece. Ive assembled a new 400 with higher compression and a mild (276) cam, as well as this AVS2 carb. What would you recommend as a starting point to ensure I can fire up and break in my cam right away and not wipe anything dry trying to fire it up the first time? *edited for typo

[@Alanpegg74]

I just installed a 1406 carb on my newly rebuilt 350. I'm running a stock type mechanical fuel pump. My fuel pressure guage is reading 3psi of pressure. Am I okay with that low of pressure or should I get a higher psi pump so I can keep it in the 5-6psi range? Ty

[@MuscleCarSolutions]

At that PSI it’s going to have a difficult time keeping up with the demand. Pressure and flow are two different things, but I’ll assume that the flow rate is also reduced. Might try another gauge to verify that it’s not a defective issue and then swap the pump. For sure run a pressure regulator that way you’re in control of what pressure the carburetor sees.

[@Alanpegg74]

@@MuscleCarSolutions ty for the input. I have a new guage coming the non fluid filled type. I took my regulator off temporarily to seeing it was causing the ultra low psi. But it was still reading 3psi without it. So I'll see what the new guage says and go from there. I know regulators can bring preassure down but not going to make more if it's not there to begin with.

[@MuscleCarSolutions]

Sounds like you’re doing all the right things to determine where the issue is.

[@shadvan9494]

I find the Edelbrock carbs tend to be too rich from the factory. my tuning method is to get the engine to operating temperature. set the timing using the total timing method with the vacuum advance disconnected. then get a measurement on vacuum and install the recommended piston spring. I then set the choke to full open so the choke will not affect tuning. the use a AFR gage like you recommended to set the Idle. I like my idle around 14.5:1 for best efficiency and lowest emissions. Then I find a nice flat open stretch of road or freeway with low traffic and cruise at 35-40 mph and take a reading, then 50-60 mph and take a reading, attempting to keep the pedal in the same place to eliminate as much fluctuation as possible. the reading should be pretty close, I use that to set the air fuel ratio for cruise. i like 14.5 to 14:1 the using that same stretch of road, I start with cursing at speed and then roll into the throttle a bit but not opening the secondaries. think of it as passing a car on the freeway. I want to see the AFR gauge drop to around 12.5-13:1 then gradually come back up as the engine increase rpm and vacuum recovers to pull the pistons down. lastly, I use test and tune nights at the drag strip to dial in the secondaries. with all 4 barrels open i want to see my AFR between 12.5-13:1. if there is any bog or hesitation off the line, at this point O increase the size of the squirters or possibly changing the springs. lastly after the car has cooled down to room temp, i set the choke per the factory instruction, and then in winter i fine tune the choke setting to make sure it starts with very little effort on a cold day. I have also found that sometimes you need rods or jets that are not included in the tuning kit. Edelbrock makes a very large assortment of rods and jets, but they are not all included in the tuning kit. I have also found that sometimes i need a summer Tune (leaner) and a winter tune (richer) to make things run right. I just document what i had it at before and then return it to that setting at the end of the season. this same process also works on a Quadrajet, you can still get Performer Q-jet parts from Edelbrock including rods, jets, springs, hanger, etc.

[@MuscleCarSolutions]

Wow. You really like your AFR on the extreme lean side. With todays fuels, I don’t know that I’ve ever met anyone who’s willing to take that chance.

[@mikeknizner6444]

Recently purchased 1969 Firebird with a stock 350 engine it has a 1411 750cfm Edelbrock carb with a performer intake, factory cast iron headers, flow-master exhaust MSD electronic ignition. Is that 750 cfm carb to big for this setup it seem to stumble a bit under acceleration

[@MuscleCarSolutions]

Mike Knizner yup. You can meter it down a little, but you can’t meter down that CFM. If it’s bone stock and just a fun cruiser, I’d put a 500 or a 600 on. The 600 would allow you to grow into it a bit. This situation you’re in is a perfect time to pick up an AFT gauge and see how rich it is as it sits. Good stuff can be learned from what that gauge will tell you. Congrats on the car. Absolutely love the first gen Camaro/Firebirds.

[@garystump1776]

I very much enjoyed your information, just got an old plymouth with 318 with edelbrock 1405 ( and year built carb 0462 how do I read what year this is

[@andrewbutton5580]

On a cammed 350.chevy with a tunnel.ram.what should the primary jets be ? Should the springs be lighter if the cam is large ?

[@haroldlucas239]

Thank you for your video. I have a SBC 383 Stroker. I'm also running a pair of Edelbrock 600 CFM carbs on top of a Weiand 671 blower. Right now my tuner has 62 jets in the front (primary) of both carburetors and 72s jets in the back (secondary) of both. We have the metering rods out but we left the plungers in. Timing is set at 27 degrees advanced. What is your opinion on this setup, have you ever heard of a setup like this. Just would like this hear your feedback if possible. Thank you,. Jr.

[@garrettgrantham7411]

Thank you great video. Got a 650 cfm avs2 for a 302 Ford 1969. Running crazy rich, I believe I'm oversized on the carb. is it possible to detune (jet/rod change) this 650 to run on a small block 302 Ford?

[@MuscleCarSolutions]

Unfortunately you can’t tune CFM. I would agree you’re probably are too big on the carb. Not much you can do. Lean it out where you can and live with the rich condition. Or make the switch to a 500.

[@salmineo3931]

I recently rebuilt my Eddy 1411 after it sat for 5 years with ethanol gas. First rebuild of a carb. Started the car, but having issues with the sound coming out of the exhaust. Almost sounds like a motor boat. I've been told it sounds like an exhaust issue to running lean. I'm using Rec 90 non ethanol for the first time. I've adjusted the mixture screws with a vacuum gauge. Getting 16 on vacuum. Idle set at 750. Very erratic response when hitting the gas. What am I missing?

[@MuscleCarSolutions]

It could be a dozen things. Start with the basics first. Timing/ignition. Fuel delivery/pressure regulator adjustment. Pop the top off the carb and make sure you didn’t leave any of the jets out. Make sure the accelerator pump diaphragm is not twisted up/cocked in the bore. Check for vacuum leaks.

[@salmineo3931]

@@MuscleCarSolutions Can you rebuild my carb?

[@MuscleCarSolutions]

That’s why I make these videos. So you can do it!

[@mattmason1694]

I just rebuilt an old Carter (1st time) and set the idle speed so the transfer slots were square. There was no amount of timing or fuel mixture tuning to get the thing to idle with them set that way - had to go several turns in on idle adjustment. Checked for vacuum leaks and actually blocked off all ports. What might I be missing?

[@tomreyn3610]

Old carters are often plagued with worn throttle shafts.

[@richardalbano523]

I was curious about my 1406 she was running great with choke closed then after 1 test ride she started running like dog crap, surging and hard to keep idle in gear. If i cover the butterfly with my hands the idle raises and smooths right out. Sprayed carb cleaner around the top plate gasket by the throttle and you can hear and see the difference on the vacuum guage my question really is this a normal occurrence on these carbs? Thing is only a few months old has no miles on it. Thanks for the videos and the help

[@MuscleCarSolutions]

You have a vacuum leak somewhere.

[@tommyyarbery379]

So I have an edlebrok 1404 every since I installed it it's ran like crap. I don't have a rpm gauge (77c10). I've adjusted the air/fuel screws a thousand times but the idle continues to hunt, ive checked timing, vacuum leaks ECT. I've installed the adapter for the 1404 on the intake. All 4 opening on the intake are about a little less than a 1/4 in blocked by the gasket(maybe that's the problem?) I've made it back fire through the carb twice and both times the truck ran fine after words. But after about 30 min it's back to running hunting. I'm at a complete loss on it. The original carb was a quadrajet 600cfm the 1404 edlebrok is 500cfm. Maybe under cfm? I went back and forth between air ratio screws idle screw and timing for around 3 hrs lol all the hoses are in the correct spot and timing is correct according to the air cleaner cover(2° for a 350) also switched it to the second hole down on the acc pump for a bigger pump of gas (which helped steady idle alot) any input is much appreciated (77 c10 350 stock intake edle brok 1404 with adapter plate to intake)

[@tommyyarbery379]

@@MuscleCarSolutions the pressure regulator I have no idea honestly, I added one after the pump before the carb recently, I have not took apart the edlebrok yet and the back fire only happens through the carb if I rev it a couple times while it's surging.

[@tommyyarbery379]

@@MuscleCarSolutions I've set and reset the timing to 2° Everytime I turn my idle up or down

[@tommyyarbery379]

@@MuscleCarSolutions no I never added a pressure regulator, everything on the engine is stock except the 1404. I added a new filter between the carb and the fuel pump when I installed the edlebrok about a month ago. There is another one before the pump that I changed about 6 months ago while I still had the quadrajet on it.

[@tommyyarbery379]

@@MuscleCarSolutions alright alright thank you very much, I'll get back to you as soon as the funds are there for me to buy parts

[@suejackson8007]

I have watched this and some other of his videos. i have a 66 Mustang, slightly warmed over 289. My old Edelbrock1406 was just changed out to a 1906 AVS2. I replaced the fuel pump that was rated between 6-8 psi. New fuel hose and filter between the pump and carb. As recommended, I added a regulator. [A cheap one at first] No matter what adjustment I made, all I got was between 3-4 psi. So I upgraded to a more expensive regulator, and still only reads between 3-4 psi. His channel says Edelbrock's like a 5-6 psi reading. Help

[@MuscleCarSolutions]

@@suejackson8007 well it’s time to verify what pressure (flow) the pump is actually producing. Then determine if the pump is defective or you have something in the system blocking the flow.

[@lannanaelyn8560]

So I'm working on a 650 edelbrock on a small block chevy it's tuned for a 400. I have watched many videos . I have picked up a vac gauge and I'm now steady at 19 psi. I have a small stumble at the time of hitting the gas at start. Am I running to lean... Or would you recommend checking the chart. I don't have a pic of the chart but am going to find one or all needed. I was thinking metering rod.

[@MuscleCarSolutions]

It’s ok to sacrifice a little vacuum to correct any problems like the one you’re having. It’s very possible that’s it’s a bit starved of fuel. I would look at making a step up spring change first. That will get your current set up to tip in faster when the vacuum in the engine drops as the load increases. You can move on to rod/jet tuning after that.

[@tommychest6159]

A great video indeed! I am about to buy a buick with a 455 engine with an edelbrock and and at cold start it is has a hunting idle, also when you hit the gas it does not pick up well, seems like it is out of power. This information might be a little general but do you have any idea what might be the problem? It it just a matter of tuning the carb or is it a more serious problem? What might be the steps to undertake? Greetings from Holland

[@tommychest6159]

@@MuscleCarSolutions Thanks for the quick response. I will try to obtain more information to narrow it down and then I would like to come back to it. Thanks alot, I apreciate it!

[@badthingsauto666]

just baught a brand new one the four barrels will not open unless i open them by hand...... I hate that sob and am ready to put my quadra jet back one any tips?

[@luizfernandopaquieli3709]

It's a great explanation! I have an Edelbrock 14053 on a Ford 302 and I couldn't remove all jets, they stuck and broke down inside of it. Did you face any issue like this?

[@cudatom9290]

@@MuscleCarSolutions How do you drain the carb. do you take it off of the motor or do you have a trick?

[@derwinrandle2682]

I having problems my 800 thunder carburetor to idle without pulling off transfer slots,help please.

[@MuscleCarSolutions]

What engine? What tuning steps have you done already? What is your fuel pressure regulator set at? What is your engine vacuum? What step up springs are you running?

[@c.pc.5805]

I have a question on the digital air fuel gauge. If your running dusk exhaust do you have one for each side of the exhaust system and how far down the exhaust do you place it?

[@c.pc.5805]

@@MuscleCarSolutions that good to know. I was thinking of building an LS motor up with a 850 on it. With a long and tall runner intake on it. With a fuel cooler in line from the tank. A trans cooler to cool the fuel as well. Then have a circulator pump with a large trans cooler on it in the back to keep fuel at a constant temp. Use a carb spacer to isolate it as well. So this way I can have a cool dense fuel charge. I want looking at several to buy. But I will wait on you to return from SEMA and see what you come up with. I want this motor to flow well and have good power. Thanks so much for your time and help with this.

[@jamesahr2634]

Running 1407, on r30 series chevy 1ton. 454 cannot get rpm lower than 900 rpm.manual shift. Hei vacuum advance.idle screw backed all way out, any advice is appreciated

[@MuscleCarSolutions]

You’re into the transfer slots. kzbin.info/www/bejne/eqG4aKOMabGcaaM

[@moncefdif6372]

great video. i have an issue with my jet boat its 21 ft aluminum with 1410 Edelbrcok marine and 350 chevy. boat starts and idles , and cruises fine but when it gets to 3600 rpm it wont go any further. if i push the throttle it it starts spiting and stumbles and have no further power . thx for the tips

[@moncefdif6372]

@@MuscleCarSolutions thanks for the comment. to be honest dont know much myself about what was done to the boat .just purchased 3 months ago from a heavy duty mechanic shop owner. he told me the boat is fine it just need new jets and carb adjustment. the boat has electrical fuel pump so i just added a holey deadhead regulator thinking it my be over-fueling but i have not taking to the water to test yet. i purchased the carb jet kit but I have not open it or install it yet because I though I will try one thing at the time to see if the issue goes away before i pour more money on this.

[@moncefdif6372]

@@MuscleCarSolutions i just run into this google comment that says "If the carburetor is "too big" then the engine will not be able to keep enough air flow through the barrels for fuel delivery to occur. Which would explain why the engine would work at highway speeds but struggles at low rpms. Jun 8, 2010" Howver, mine is the opposite , it runs fine in low speeds but struggles at higher speed.

[@moncefdif6372]

@@MuscleCarSolutions will do thx again.

[@hdld7371]

what spring do you use if you pull 20 inches of manifold vacuum?

[@MuscleCarSolutions]

Start with the silver spring.

[@cordelmar]

My engine back fires around 1400 to 1600 rpm, is it wrong placed sparkplug cable or the carb needs bigger jets for more fuel?. I Need help with this.

[@MuscleCarSolutions]

@@cordelmar hard to guess with a limited amount of information but if it’s backfiring it’s probably a lean condition. At that RPM it indicates the possibility of a vacuum leak. What carburetor and intake are you using? What’s your initial timing set at? When was the last time to carb was cleaned/serviced? What is your fuel pressure at the carb? Does it backfire at any other rpm?

[@carls72dart]

Quick question... I have the edelbrock 1813 & purchased the 1841 tuning kit for it. I have the tuning chart for the carb & it says the numbers in black should be obtainable with that kit. The kit does not have the meter rods it calls for in the kit. Have you come across this before? Can I just move up the next metering rod to richen it for power? Thank you

[@carls72dart]

Thank you for getting back to me. Correct, I'm looking in the shaded area for 1 stage up rich on the power side & the number on the sheet for the rod, does not exist in the kit. I'll reach out to edelbrock & see what they say.

[@carls72dart]

Tech support is shipping them out today.

[@Squares.SSs.and.Bowties]

In tuning my engine timing, carb etc I cant get vacuum level any higher than 16 when (as I understand) 18 is a target minimum. My engine builder is telling me the problem is in carb set up. Can you provide a direction for me to explore? Fyi the camshaft is not a stock grind but is very mild. It is a 350 chevy with stock heads cr is +/- 9. The engine starts well and idles ok. It throttles up and down nicely also. I feel she's holding back under load but not hesitating or pinging. Im not carb savvy at all but really do want to get there! Please help. Thanks!

[@crazyhorseDOC59]

I'm using anf AFR gauge running a 650 AVS2, in cruise mode running 13.5 throughtout the RPM range up tp 6000, however if I go wide open throttle after about 3000 RPM the AFR goes to 25 or more...way to lean. When I go richer on the primary side it runs 8.0 to 10. without any change at WOT, still runs lean. went richer with the seconday jet...no change in WOT Engine is a SBC 350 has about 3000 miles.

[@MuscleCarSolutions]

How have you adjusted the AVS?

[@crazyhorseDOC59]

@@MuscleCarSolutions currently at 7 for model 1915 on pink spring .104 secondary jets, minus 1/4 turn less tension on the secondary plate.

[@MuscleCarSolutions]

@@crazyhorseDOC59 there we go. Add tension to the AVS. kzbin.info/www/bejne/nqPalJijmtxrnZo

[@crazyhorseDOC59]

@@MuscleCarSolutions that was the only video of yours I had not seen. All your videos are very well done. Great productions. Thank you.

[@MuscleCarSolutions]

@@crazyhorseDOC59 glad they have been helpful! Let me know if that AVS adjustment helped.

[@TheHomy70]

Black sparks plugs & poor gas mileage mean too rich...use the chart to change metering rods only? Or would a change in Jet size too be needed?

[@sandalsinak6829]

This is more than likely a stupid question but I just purchase the AVS 2 ( 1906 ) for my 72 k2500. I looked up the calibration chart you had mentioned but there is no graph for the 1906. It only goes to the 1825 and 1826. Is there a graph for the AVS2 1906? if so could you lead me in the right direction. This video answered so many questions, thank you for your time sharing the knowledge.

[@MuscleCarSolutions]

If you go to the Edelbrock site and search the 1906 you’ll find the pdf instructions link on that landing page. You’ll need to scroll down 3/4 of the way and you’ll see the tuning chart for the 1906. Please don’t hesitate to ask me any questions. Always glad to help!

[@sandalsinak6829]

@@MuscleCarSolutions You are awesome! I found it. There is so much information on there. I am currently on the oil fields in alaska. When I was home last week my holly started giving me issues. I have never really figured out how to properly tune it. So i decided to buy the AVS2. I am really excited to put it in. I just hope I can dial it in nice. I just rebuild my transfer case so I am hoping I can do this :) Thanks again for the help my 72 k2500 I hope starts running a lot smoother. It has the 383 in it also.Thanks again. Is there a way I can contact you if I have any questions? I don't wanna bother you though but Im sure I will need some clarification when I dive into this. Take care and thanks again.

[@MuscleCarSolutions]

Just drop me a note here and I’ll be glad to help! Best of luck to you. If you tackled the transfer case, you’ll get the carb dialed in no problem. You can also check out the other Edelbrock tuning videos in have in a playlist. Might give you some more tips and insight on your tuning.

[@sandalsinak6829]

@@MuscleCarSolutions Thank you sir!!

[@Michael-qy1jz]

Does it matter if you use the PVC port for Brake Vacuum???

[@MuscleCarSolutions]

Use the rear port for its intended purpose. It’s there for your power brake assist. Front is for PCV.

[@maximuswedgie5149]

This is a fantastic video that I’ve been looking for. Tomorrow morning I go pick up my 1408 or 1480? Edelbrock tuning kit. I had no idea where to start now I do thank you very much. I put a new 383 ( with bigger cam and roller set up)in my Mopar and I got a terrible stumble off the line. I can’t even put it in gear unless it’s almost 1200 RPMs at idle without it dying. I will be referring back to your video and I will hope that my kit comes with that book. If not I will download the PDF as you said. Thanks again for the great video sir

[@MuscleCarSolutions]

Well you’ve got some work ahead of you but the good news is with some patience and a little understanding, you’ll be able to get it running and driving much better. Don’t hesitate to ask any questions if you get stuck. Happy to help if I can.

[@MuscleCarSolutions]

I’ve got a ton of Edelbrock carb videos and fuel system set up in a playlist. You might find some of those useful too. Good luck!

[@maximuswedgie5149]

@@MuscleCarSolutions I will definitely check the other videos out👍🏻 thanks for the reply

[@larrylewis2674]

Great video!! I have a couple questions. I have a 38 Ford 2 door coupe with a 327 SBC and an Edelbrock AVS2 650. Since I got the car about 4 months ago. I bought the AVS carb, HEI distributor, spark plugs and spark plug wires, new standard fuel filter set up. I also have an in tank fuel pump, but want to change it as it is leaking at the gasket every time I fill it with gas and smells through the trunk. I have a slight hesitation at cruising speed. If holding a speed above idle it will slightly hesitate (not every time) until I accelerate some more. I bought the calibration kit and was hoping to send you a photo of the chart to make sure I am reading it right. So questions..any thoughts of what is causing the hesitation? Also, I am planning to use your suggestions on filter set up. Can you recommend Micron filters and a regulator. I am thinking of eliminating the in tank pump and going with an in-line pump. Any recommendations on a fuel pump. Not sure if I can send the calibration chart via photo on FB. Do you have an email that you would share?? Thanks!

[@larrylewis2674]

I know the tranny is a turbo 350, all I now about the cam is whats on the original build list from the late 90's that it's "aggressive", balanced/bored 40 over, and a Holley high rise aluminum manifold, I don't now the compression ... I can check with the mechanic who has helped with the upgrades? I have the calibration chart and if I'm reading it correctly the closest reference number moving to the right and up in "Rich in Cruise Mode" is "11" #1430 jet and #1455" Metering Rod. Just not sure if that's how I should be reading the chart though? Thanks for your help!

[@KyleClarkMountainMan]

Help!!! I have looked for hours and hours online and it's been decades since I messed with a carb. haha. My AVS2 offroad version is sending fire out carburetor under full throttle. It runs great if i don't open secondarys. Is to too rich? Do i need to adjust the jets? Do I adjust left or down to lean it out under full throttle? Thanks a ton!!!!

[@MuscleCarSolutions]

@@KyleClarkMountainMan there are a dozen things that could be wrong. When you say fire, do you mean it’s forcefully backfiring or just randomly catching on fire? I’ll assume backfire. Timing, incorrect lash on rockers, distributor/plug wires installed wrong. Over fueling/too high pressure/incorrect float setting/garbage holding needle open. Pick one and start eliminating potential issues.

[@KyleClarkMountainMan]

@@MuscleCarSolutions Correct. It is backfiring. Runs amazing at idle to 3/4 throttle as long as I don't tip into the throttle to hard is even revs great. Timing is good and have played around with it several degrees. Fuel pressure is about 5psi. I'll replace wires and cap and go from there. thanks for the help!!!

[@MuscleCarSolutions]

@@KyleClarkMountainMan unfortunately, “timing is good” doesn’t mean anything and generally it isn’t. What is your all in timing set at and when is it at full advance? I’d be looking closely at that and the other potential issues I mentioned with fuel delivery.

[@KyleClarkMountainMan]

@@MuscleCarSolutions I'll take a more detailed look at the timing. It didn't backfire with the old carb but it did flood out. Thanks again!!

[@serialgrillaz6669]

I have owned a carb for all of one week now and have a wideband gauge, its reading well into the 10s at wide open throttle, 4th gear 80kph is there a way to accurately calculate what secondary yet i would need rather than going down in increments? The episodes are great btw. Half way through allready

[@MuscleCarSolutions]

Always take small steps. As you've figured out, 10 is WAY too RICH! Yikes! Its the quicker way to tune is to take those small steps. It all really depends on the size carb and what the engine is. You can check out my video on what size carb to run for a simple equation plus some additional tips at the end on how to pick a size. Might be useful to determine if what you have is going to be your best option. Dont hesitate to ask any questions. Always glad to help.

[@serialgrillaz6669]

@@MuscleCarSolutions thats another thing thats throwing me off, its a 350 602 (circle track motor) it makes 350 crank, I would think the 600cfm edelbrock would be pretty close from factory. It has been sat for 3-4 years though

[@lukemiller2895]

I'm about to order a new avs2. It's going on a near stock 454. What's your recommendation on cfm? From what I read and ive heard I was going to order the 800cfm... any thoughts?

[@lukemiller2895]

Is that the carburetor you would order for a stock 454?

[@raygee1138]

I'm running a pair of Edelbrock Thunder Series carbs (1803 & 1804) on a Pontiac engine. These are part of an Edelbrock top end dual quad kit consisting of the carbs, intake, cam, lifters & rocker arms. I've installed a pair of Edelbrock #8722 1/2" wood spacers under the carbs to alleviate heat soak. The problem I'm trying to overcome is a very rich idle, the tailpipes are black and if I'm in the garage with the car I could die! I've adjusted the float levels to stock and a little less with no difference, if I went too low the car would stall when I made a hard turn or fast stop. The carbs are set up with the as-supplied .086" primary and .077" secondary jets. I'm using a stock mechanical fuel pump and need to check the pressure output-at what point does fuel pressure overcome the needle/seat assembly? Thanks for your time and help.

[@raygee1138]

@@MuscleCarSolutions Copy that-and the good thing about this set-up is the carbs are only 500 cfm each, less than needed for the engine alone, and with 1000 cfm available at WOT there's more than enough for power runs. The car has no drivability issues, well, there's one but that can wait till later to diagnose. I've read that Edelbrock offers spring loaded needle/seat valves to avoid shock encountered by offroad use, maybe they'll help with a lower float level. Also, would you recommend leaving the original float drop setting or changing that as well? Thanks-

[@raygee1138]

@@MuscleCarSolutions I verified that the mechanical fuel pump is supplying a steady 5-6 psi to the carbs. Next step will be to adjust the float levels, do you have a recommendation for how much lower to go than the 7/16" specified by Edelbrock?

[@peteloomis8456]

Ray if your running a very hot cam with a lot of duration i have seen some Edelbrock carburetors run rich at the idle circuit because the vacuum is too low from the cam shaft duration so what do guys do is drill a small hole in each primary throttle plate to allow more air to come through at idle circuit idle ! Had a guy at the shop i worked with that had this problem on a 70 440 Challenger that was doing the very same thing because he had this radical high duration cam shaft and with small incremental changes on the hole fixed drilled in those front throttle plates he was able to get it running much better to a point it not only pulled harder out of the hole it also wouldn't burn your eyes at idle in the shop anymore . He tried lowering the floats as well as leaning up the primary jets but that still didn't do much until the holes were drilled !

[@CLINTSTER77COX]

Great video! You said we could leave a. Question in the comments. We put a new 1805 thunder on a 305 small block . At launch with foot brake it stalls ? Any idea where to start . Any comments appreciated. Ty

[@CLINTSTER77COX]

Bone Head sorry 1805 I believe. 650 thunder with manual choke

[@CLINTSTER77COX]

Bone Head the Edlebrock chart said down to 283 . We have headers and performer intake with power glide , 4.56 9 inch ford . Stall is 1800 I think . Can we lock out the secondary somehow? Just to give it a try ?

[@CLINTSTER77COX]

Bone Head electric water pump and fans but as far as the core components stock except zero emissions and msd multi spark box

[@CLINTSTER77COX]

Bone Head man I thank ya . It’s been on the car for over a year . My dad is an old timer and spent 20 years building this bracket car and went to the track for the first time and died on the line . It started right back up and did 75 mph in the 8th mile . You gave us somewhere to start . I think the original idea was to stick a 383 in there and swap everything over so we don’t have to buy anything twice but not having anything to start with . I guess I could put a 75 shot nitrous on a one second timer at launch and still stay budget friendly. Thanks

[@CLINTSTER77COX]

Bone Head here’s the chart Your right because it’s not talking about a stock 305 . advertising.edelbrock.com/Literature/Misc/EDL_Carb_Application_Chart_03186.pdf

[@DesertRatFabrication]

And also what do you mean about the set-up spring to control the transition between cruise and power, thanks

[@DesertRatFabrication]

Hey Bone, I am about to rebuild my Edelbrock 1406 fuel pressure is good, will be changing filters as well, the biggest problem I was having is a chugging when driving on a flat surface at about 10 miles an hour, not real bad but noticeable, with that being said as soon as I give it some gas snaps to life, so I thought I would just rebuild the carb, sense I just bought the truck a short while back (55 chevy big window), what do you think, thanks Mike

[@DesertRatFabrication]

Bone Head right on, thanks, should I try it the way it is after the rebuild first , probably ya

[@DesertRatFabrication]

6 psi

[@DesertRatFabrication]

6 psi

[@DesertRatFabrication]

But I only have the 8139 filter

[@DesertRatFabrication]

Is it ok to put both filters and regulator under the hood