Killer video. After years of tuning Holleys I'm gonna try the AVS2 on a AMC 360 I'm building for my CJ7 and your tuning tips are really going to help me. Thanks!
@ethanrabideau74029 ай бұрын
Did you get it to run well? Our AVS2 always comes out of tune as soon as I floor it a little
@steelcitycaprice.8995 ай бұрын
👍🏽😎 awesome straight forward illustration. I've been battling my avs and not knowing what direction i should take. Now i see how to approach my issues. 🏁🏁🏁
@dtread95432 жыл бұрын
I have the 650CFM AVS2 on a stock peanut port 454 in my square body. 33 tires, 4.10 gears, 4L80E trans. Out of the box with just the idle screws adjusted I'm getting 12 around town and 13.5 on the highway. It's the best carb I have ever had.
@MattsGarage2 жыл бұрын
I like it too. I have since put a sniper on the scout but plan on putting the AVS2 on the Bronco.
@stephensaasen85892 жыл бұрын
I have an AVS2 1906 on a FE390 with RV cam on F250. It's given me the best mileage yet out of a Quadrajet and a 1406 Edelbrock 600 cfm. I got 8.5 in town on the Q-jet. The 1406 gave me about 9.25. The 1906 gives me about 9.75mpg in town. It does much better on the highway. Almost 14mpg. I wish I could get it over 10 mpg in town but I'm thinking I'll need to get my cam degree to zero. There is only one set of timing marks on the chain sprockets but since the cam was installed 30 years ago, I'm inclined to think it's ground as much as 9° retard. I'm thinking that cam may be making it suck alot of air because I'm in process of tuning it. I get a stumble mid range RPM. I'm having trouble with it running bad after I let it set then start warm in really hot weather above 88°F, so I'm inclined to think I'm having too much heat trapped in the bowl and it could be trying to boil. I put in a 37x65 meter rod down from the stock 37x70. It ran better until I restarted it on a hot day and it just ran crappy and stumbled all over the place. I'm waiting for the weather to cool so I can do more tuning and eliminate the potential boiling issue.
@Faith0929ROKАй бұрын
@@stephensaasen8589did you add .5 to 1 inch spacer so carb is not touching the intake which may boil your fuel? Also try drilling a 1/8 holes in your main primary butterflies to draw in more air during idle for better mixture during idle.
@Faith0929ROKАй бұрын
Old school timing trick I use is, without the light, just use vacuum gauge, advance the distributor to the highest vacuum, retard about 1hg vacuum, set idle mixture to highest vacuum, than back off on idle a little, look at the timing. This way you know you are getting the most volume in cylinder. Go for a drive, open her up, if pings, back off on timing about 2 degrees, set mixture, set idle, try again. Anyone with cam, you should drill two 3/32 or 1/8 holes in the primary for more air during idle. It does not hurt anything and mixture screw will respond better.
@stephensaasen8589Ай бұрын
@@Faith0929ROK yes. I have the original Ford spacer. I bypassed the heater hose that usually runs coolant through the spacer to warm it up. I even added to that the very thick quarter inch insulating gasket. A friend of mine thinks I might have a fuel pressure issue since they seem to like 5lbs.
@jamestally7184 Жыл бұрын
Excellent information, thank you very much for making it simple as I am not a carburetor mechanic by any means, I’m running a 390 FE motor in a 1974 F-100 with a fairly lumpy cam at about 450 to 475 hp. My issue is at launch with this new AVS2 650cfm carb it stalls so I am going to try changing that pin location on the metering block and if that does not work I am going to buy some new springs, excellent video
@matthewgorgoglione549214 күн бұрын
Ok yep after research and development, I figured her out, with your set up should work great to, just put #8 springs in, the on adjustment needles up front carb go full in and one turn out
@79c152 жыл бұрын
I absolutely love my avs2 0 issues and my bace timing is 11 btdc and it's got good power with great economy
@scottfuglie94172 жыл бұрын
note when setting the idle jets can you get it to go rich when backing them out ,if not the idle circuit feed is to small and there is not enough fuel for transfer circuit between the idle and the start of the main circuit ,so if you are coming off the idle slow and loaded some it will bog some some times pop , note when adjusting the accelerator pump for more fuel will help under faster accelerator movement , but will still be there under slower movement .
@HorsepowerHouse Жыл бұрын
You can tell by looking at the spark plug electrode if it's rich / lean. And by how the car sounds and feels and smells. Gauges aren't necessary.
@kidnmejoe Жыл бұрын
I will give you one thing to remember for when you are tuning. only do one thing at a time and take it for a drive. As you want to know what your engine is doing per different circut in your system.
@johnnyturbo84602 жыл бұрын
Great how to video! I'm tuning my AVS2 as well
@MattsGarage2 жыл бұрын
Thanks Johnny!
@johnnyturbo84602 жыл бұрын
@@MattsGarage 😁👍
@79c152 жыл бұрын
Also that little stumble could he your secondary valve over the rear jets. Get that adjusted right itll be fine. Had mine doing that.
@AllanSmith859 Жыл бұрын
I'm no expert but what ever your vacuum reading is, you divide that by 2 and that's what step up spring you should install. So the silver springs is what you need.
@alfredpaz2805 Жыл бұрын
I jus installed mine in a sbc 400 , luv it from the get go, grt carb,
@campnoutdoors1621 Жыл бұрын
Great Video!!! Thanks
@RatelLaw2 жыл бұрын
Thank you for sharing.
@benkeeler88532 жыл бұрын
Too many times I've had the wrong carb for the manifold. If you have a spread bore manifold which is what the performer is, you should run a spread bore carburetor or a q-jet. Edelbrock square bore carb should be on a square bore manifold. The adapter is still an issue. In my opinion. The rpm performer manifold is made with square bore. Easiest way to check without removing the carburetor is the performer manifold usually has an egr port and the rpm performer does not. The q- jet is a good carb for a truck and runs really good when paired with Edelbrock performer manifold.
@scottsheppard56212 жыл бұрын
Thank you for that
@stanriley20202 жыл бұрын
I have the same carburetor on my 1991 C1500, 5.7, 5 speed manual, lower end all stock. I installed Edelbrock E Street 64cc combustion chamber heads, I be leave that 76cc was factory heads for that motor. I also replaced the cam/lifers with a Summit Racing mild cam, more than stock though.
@MattsGarage2 жыл бұрын
I did the same thing I swapped out the original 76cc smoggier heads for 64cc vortec plus a lunati cam. The motor is much healthier now
@stanriley20202 жыл бұрын
Also installed steel roller rocker arms, 5.1, stock ratio. Currently using 75-42 rods with 401 jet on the primary, secondary was leaned out with 0.092, which is a 392 jet. My idle mixture screw’s are out 3/4 turn. Also 1 step stiffer on springs which makes the secondary part of the rods starting to kick in at around 7 inches of vacuum. I installed an AEW air/fuel ratio gauge to help me to get to this combination. WOT I’m around 11.5 when I first get on it, then it leans out closer to 12.5. My idle vacuum is around 15 after warmed up and idle mixture screws, again, at 3/4 turn out, which mak s my AFR around 13.5, give or take. Also I’m running a Weind aluminum intake, factory HEI Chevy distributor, which is a Chinese made one. Word of advice, replace the magnetic pickup coil and the ignition module with a good quality one, preferably factory GM parts. The Chinese electronics on them are junk. I had a MSD Street Fire ignition control box installed, which eliminates the ignition module in the distributor, but had an issue with a hole burned through the rotor cap, thus grounding it out on the distributor shaft, = truck wouldn’t run or bad miss. Bad miss, failure to run first happened with the coil, then the pickup module. Lesson learned on E Bay parts not being American made. Anyways, like everyone else, I continuously experimented with different combinations, springs, jets, metering rods, trying to get the AFR readings that I was looking for, finally setting on the combination previously mentioned. If your battling with tuning a carb, best tools to have is a vacuum gauge, and by all means, an AFR gauge, a broad band one. Hope this helped anyone.
@oscarvillarreal8951 Жыл бұрын
@@stanriley2020 what kind of cam did you get from Summit name brand? And do they work fine?
@tonycolca22413 ай бұрын
With springs be sure they are holding rods down at cruise that's why I said rods instead
@BPattB Жыл бұрын
Have you adjusted when the secondary air flap opens? I had a definite stumble when I would go from cruising and hammer the throttle wide open. I tightened up the air flap which made it open a little bit later. I guess what was happening was the air flap would open and the car would go lean for a second. I may actually try larger jets in the secondary and loosen the air flap up again.
@tonycolca22413 ай бұрын
Instead of springs I would change metering rods but without an afr gauge itvwont be better than a good guess.
@GregBallard-e1pАй бұрын
Never heard of setting timing with vacuum advance hooked up. What rpm does your 32deg total advance come in. when does the vacuum advance come . Timing is the main culprit for carb problems.
@mikewarren5262 Жыл бұрын
i see you have the rear carb studs in the inside holes i cant use the outside holes the washers and nuts dont fit behind the carb the front has more room
@denniskwasnycia19502 жыл бұрын
I got the same carb for my 460, but that engine is still in the works. I imagine that with the 460, I would have to automatically go with the #8 spring to start? It's built for torque, not a lot of hp. Low RPM range cam.
@MattsGarage2 жыл бұрын
Great question and I don’t want to pretend to know the answer. I will guess though: not necessarily because of the high torque of the motor it may not drop vacuum as much as it’s wimpy small buck cousin. You’ll have to trial and error is my opinion. It’s easy though. 10 minutes if you take a coffee break.
@broncobrady31212 жыл бұрын
Thanks for the video I have a 71 Bronco 302 with an Edelbrock 1406 and have had the same issues for 20 years After changing carbs 3 times 2 distributors and cam I was thinking it was a bad engine I am going to rebuild the carb and change the springs today I’ll let you know how it goes
@MattsGarage2 жыл бұрын
@@broncobrady3121 please do! Feel free to email me at Mattsgarageshow@gmail.com
@vincemajestyk94972 жыл бұрын
There is no 'power valve' in those carbs. The 'Cup' is called a power piston. I'm surprised that on such a mild engine it didn't work out of the box. I have an engine a little bit bigger than yours (383 Chry), mild street cam (Crane HMV272), dual plane intake, ported heads big valves, 2.5in duals, Jacobs ignition, and it pulls 15" vacuum smooth idling. I literally took it out of the box, adjusted the idle and MAYBE 1/4-1/2 turn out on the mixtures from where they were. The exact same carb as yours. It's also WAY better than the Carter 750cfm Competition series I took off. You're supposed to adjust for best lean idle so the plugs don't load up. Find the highest Vac and RPM then go in about 1/4 turn in and raise the idle up to specs on the emission label. The other thing is these carbs have annular boosters so you probably need to back off on the timing. That cam sounds OK for your truck. I don't think you'll notice much by swapping it.
@tomreyn3610 Жыл бұрын
Pulled my 800AVS2 out of the box. 1 mixture screw was 1 3/8 turns, the other was 3 1/2 turns out. The air door was set up w 2 1/2 turn preload and the manual stated 1 1/2 is the default. I had a feeling to check it. The floats were spot on.
@vincemajestyk9497 Жыл бұрын
@@tomreyn3610 I bought mine 4 years ago when they first came out. The screws and door were as per spec. Never checked the floats but I have no reason to believe they're off. I don't doubt there are quality issues everywhere these days. I think they only had 1 or 2 sizes when I bought mine.
@hoscba2 жыл бұрын
Did changing the springs help? I've got the exact same issue in my 80 Camaro. Running a 350 SBC, Edelbrock AVS2 and Summit K1103 Cam. Idles fine, drives around fine. But the moment I kick it in the guts it stumbles and pops. I've adjusted the total timing with an adjustable light. Had the initial timing at 10. I've recently increased the pump shot and it stumbled less, but still bogs....it's bugging me.
@MattsGarage2 жыл бұрын
Sorry for the late reply. They definilety helped but still not perfect. Will need to keep tuning it but it's slated for being put on the 302 for the Bronco.
@hoscba2 жыл бұрын
@@MattsGarage all good. Nice! I ended up putting the 7hg springs. Readjusting the AVS2 secondary flap tension and increasing the pump shot up to the highest level and it doesn't stumble anymore. Only now it's less fuel efficient as a daily hahaha
@yusuffrahman2858 Жыл бұрын
@@hoscba on the 1906 I've been having really good luck adjusting the spring tension on the secondary flap. Each time I tighten it it gets better. Still in the process of getting rid of that stumble altogether. The air is rushing in faster than the fuel. Seems kind of absurd but taking some air out of the equation will actually help this issue. T15 torx to loosen the lock screw, big flat head. Counter clock wise is tighter, clockwise is looser.
@shortattentionspangarage13122 жыл бұрын
I believe the biggest problem with people who tune carbs is they are NOT using a Wideband Oxygen Sensor to tell them what the AFR actually is. I keep hearing, "It feels rich..." or "I think it's lean..." but the reality is they don't know. AFR meters can be had for $150 from AEM and they're invaluable when it comes to tuning any engine.
@MattsGarage2 жыл бұрын
I agree with you.
@11122233331112 жыл бұрын
I never needed one back in the day...they didnt really exist.
@chaeg54772 жыл бұрын
Try the accelerator pump nozzles, worked for me
@stanriley20202 жыл бұрын
Please read the reply on my previous post. More info input there.
@RastusMcbride2 жыл бұрын
I miss my scout II.
@douglasknutsen Жыл бұрын
What do your spark plugs tell you ? What port on the carb is the vacuum advance plugged on to ? Have you thought about lighter springs for your mechanical advance ?
@11122233331112 жыл бұрын
I never had so much trouble. I got this tip in stumble too with a 1406. I rebuilt it, messed with timing, springs rods, fuel pressure. it idles then it runs rough at any time it wants too. I ordered a 1906 and its going right back if it doesnt fix this crap. I've had so much trouble its unbelievable
@MattsGarage2 жыл бұрын
Been there. That's super frustrating. It's probably something simple you'd never think of. Good luck getting it figured out.
@11122233331112 жыл бұрын
@@MattsGarage it was all the distributor. it was arcing inside from carbon dust for some reason the carbon button was wearing very fast and raining carbon dust. unreal. also alot of timing chain slop but 100% the distributor. also new rotors are coming with the conductor tip bent up to the sky and too far away from the contacts.
@MattsGarage2 жыл бұрын
@@1112223333111 That’s why they say 70% of carburetor problems are ignition problems. Glad you got it figured out
@scotthorn28683 ай бұрын
I have the AVS2 for 5 months and I have the screw that lowers the Idle all the way out not touching and when I drive my nova I have to put it in neutral and rev real fast to get the carb to idle back down at a stop light it’s like something on the passenger side of the carb is hanging or something how can I fix this please?
@MattsGarage3 ай бұрын
That sounds like timing or do you have your vacuum advance on manifold vacuum? I’ve struggled with that too and it was a combination of timing, vacuum and the idle mixture screws.
@tomreyn3610 Жыл бұрын
Did you ever move the pump lever? Drill out and old AFB squirters and swap it out. More torque? - Advance your cam 4 degrees.
@MattsGarage Жыл бұрын
I have since switched to Sniper on the Scout. This carb will go on the bronco and I’ll tune it to that 302.
@JoJo-209-11 ай бұрын
Got the avs2 650 cfm for my 327 sbc Vega about a few months ago, it runs well when warmed up but can be stupid rich at idle when cold and give that hesitation sometimes like you were saying.. it's got some double hump heads, a decent size cam, edelbrock intake, 3.73 gears in the back .. I didn't even know about these springs, would you think I'd have to step up to the 7" like you did? Or just leave it because it's a small light car? Idk lol I'm 26 and just into this carburated engine scene.. get kinda lost sometimes
@MattsGarage11 ай бұрын
I still get lost myself. If it’s rich cold then that probably means your choke is too aggressive. It’s reducing air to make the carb richer (therefore happier) when it’s cold. If it’s set too aggressive then you get very rich.
@danielesilvaggi Жыл бұрын
Mine seems to act like yours ever since I put the AVS2 in a Edelbrock performer dual plane intake but mine just smells really rich. How have you got yours running better since this video?
@MattsGarage Жыл бұрын
No, I put a sniper on the Scout. I plan on running this carb on the Bronco though and will be tuninig using an O2 sensor. I'll try to make a video about that but it won't be for a while. I'm still in paint and body.
@federicocabarle93172 жыл бұрын
So how does it perform off road steep hills etc. great video
@MattsGarage2 жыл бұрын
I took it off road once before I switched to Sniper EFI (always the plan). It ran fine generally but it gets really rich at altitude. I didn’t do any super extreme off camber, but it never stalled on my. Again, just super rich at altitude. That’s the main prob with carbs in general off-road in the mountains.
@iainhartge1979 Жыл бұрын
you would need the 1916 vs 1906 for off road
@iainhartge1979 Жыл бұрын
@@MattsGarage you would need the 1916 vs 1906 for off road
@tomplucknette5941 Жыл бұрын
Matt, could you video fuel pump and regulator?
@MattsGarage Жыл бұрын
Hi Tom. I used a Tanks In. PA-2 in tank pump. The regulator is just a standard Holley carburetor regulator. It's a simple system. The work is just getting the tank retrofitted safely for the pump. I'll have a similar set up on the Bronco which I will show in an upcoming episode in the next month or so.
@hotchihuahua1546 Жыл бұрын
This carburetor is to large for your application . Based on the cubic inches you should be using a 500CFM rather than a 650CFM carburetor .
@Donny.C.wlWilliams Жыл бұрын
just out of curiosty what is 10 drgrees of vaccum ?
@MattsGarage Жыл бұрын
What do you mean? Are you asking what vacuum advance is? That’s a complicated answer, but basically when you have high vacuum, it pulls an armature in your distributor that advances the timing by some amount. Usually it adds 10 degrees of timing. If that doesn’t make sense I suggest watching some basic videos on timing advance.
@HorsepowerHouse Жыл бұрын
You need to go back to the beginning of studying the basics to understand vacuum etc.
@michaelcannizzo10762 жыл бұрын
What CFM is the carb?
@MattsGarage2 жыл бұрын
650. It’s too much carb
@michaelcannizzo10762 жыл бұрын
@@MattsGarage sorry you did say that real quick at the beginning, I just missed it. I promise its not too much carb. Not sure your cam specs but I have a 350 with ZZ4 cam (208/221) and Fast Burn heads which are a little step up from stock Vortecs. I had same issues and I found those pops to be rich spots not lean spots. Get the accelerator plunger out of an 800 it has a stiffer spring and put that in. Try going leaner on the pump shot as well after you swap that accelerator plunger. Its hard to discern a lean bog from a rich bog because too much fuel will choke the engine. You are on the right track, 100% get an AFR gauge totally necessary and takes the guesswork out and will show you the difference between a rich and lean bog. I have mine running 14.0 idle about 13.8-14.0 cruise and 12.8 WOT. Totally doable but get that AFR Guage in there so you don't pull your hair out. Let me know if I can help you any - this carb is outstanding once you dial it in. I ripped out my MSD Atomic EFI and the car has never run better.
@MattsGarage2 жыл бұрын
@@michaelcannizzo1076 great tips. I’ve since out on a sniper (haven’t done a video on it yet) but I’ll keep your notes for the next thing I put the carb on.
@michaelcannizzo10762 жыл бұрын
@@MattsGarage Good luck with the Sniper. I'm sure its good, but it didn't work for me. I went from the MSD to Sniper before I swapped in the AVS 2 650. Holley threw their hands up - could not get the car to idle right and could not get it to run right, its almost like it wasn't reading the distributor. Between sending in data logs, waiting for call backs, chasing them down it drove me nuts when all I wanted to do was just drive the car. Hope it works for you, its a pain to troubleshoot and work on when the stars don't just align.
@MattsGarage2 жыл бұрын
@@michaelcannizzo1076 that sucks! Mine works great