Initial Carburetor Performance Tuning

Before you can start tuning for all out performance, you need to establish a baseline that compensates for your engines individual characteristics and fuel distribution qualities.
Here's how we handled this on our Plan Z Slant Six.
#SlantSix #Mopar #UTG
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[@donjohnston4215]

Been working on cars since before I got my license in 1980, turned a wrench for a living for years and have built dozens of very successful race engines. I consider my knowledge of carburetion and especially Holley carburetor‘s at a very high-level and don’t get schooled by many people. But I was highly impressed with your diagnosis and explanation of what was going on in your slant six in today’s video. Would enjoy very much picking your brain and doing some bench racing with you. Hot rodding needs passionate people like yourself and I to help carry it into the future.

[@UncleTonysGarage]

Thank you Don, I much appreciate that.

[@tarstarkusz]

How did he get this engine to 12:1? That doesn't sound right to me.

[@SweatyFatGuy]

Is this Don from DCI of the Tiger and RA V fame?

[@pookysdad4884]

@@tarstarkusz I think he means air/fuel ratio, not compression.

[@UncleTonysGarage]

@@tarstarkusz It's 11to1. .100 off the deck, .110 off the head. .022 head gasket

[@TinManKustoms]

My machine shop teacher from high-school had a dart with a slant 6 and he built a custom intake and ran 6 motorcycle carburetors. With this setup he was able to tune each cylinder to make the most horsepower. I wish I could track him down to show you how it was done. That car ran lows 10s in the quarter mile before they told him he had to put a roll cage into it.

[@rogerlizama1326]

I guess those where 6 carbs from Hondas or Yamahas between 600 - 750cc. Would be interesting to see Keihin CV carbs or Mikuni flat slides carburetors on a Slant!!

[@christophersambuco9414]

I saw something like that in a magazine once. Cool idea.

[@pookysdad4884]

But bike carbs don't have accelerator pumps...or do they? Maybe with individual runners, you don't need any?

[@watsisbuttndo829]

@@pookysdad4884 mechanical bike carbs are available with accelerator pumps but i would personally get the latest model Constant Velocity style. Mikuni sidedraft CV of 90,s suzukis were long lasting ,reliable ,easy to tune and very responsive. I have a pontiac That has a dry style intake manifold that i am very much considering running two banks on a crossram style bike carb intake.

[@2000freefuel]

@@rogerlizama1326 yeah you can get Harley CV carbs now for CHEAP!

[@bigbear5510]

When I use to buy plugs for my slant 6, I ran the plugs just like you're going to. You wouldn't believe the looks I would get from the guy or gal behind the counter. Even though it was a stock engine I had the same issue with the plugs when I did the first tune up on it. Can't wait to see and hear how Plan Z runs now.

[@leemarshall5840]

Uncle tony ive had to deal with the same issue on slants and ford 300's. Instead of staggering the jets the optimal way to do it is to get a spacer and mount the carb "sideways". Do this and the fuel distribution will be much better due to how primary and secondarys work on a holley.

[@gorkzop]

I've seen people doing this with a 2bbl conversion as well . Putting the carb sideways and welding a wall inside the manifold.. creating a dual plane intake manifold!

[@UncleTonysGarage]

This carb is mounted sideways as per the intake manifolds original orientation. It is known to have terrible distribution right out of the box

[@tedesco455]

@@UncleTonysGarage That carb is mounted the standard direction. He means turn it 90 degrees.

[@ZEPRATGERNODT]

Great idea.

[@grahamgeiger3206]

I ran into the same problem with a Holley 390 on a Chevy 292. Primarys on the outside secondarys on the inside. Engines a mild performance street engine and made a noticable difference in driveability. Full race it might not matter as much though. Worth a try in my opinion regardless.

[@onesecureone]

Lots of people talk shit about tuning Tony just jumps in and doe's shit Its called test and tune It is a non stop game we play

[@UnityMotorSportsGarage]

The firing order can effect cylinder distribution as well... All great points Tony!

[@UnityMotorSportsGarage]

@Made By Nobody Famous I couldn't tell you...

[@andyreiwitch8845]

Had this issue on a 22R motor... Raised the Weber 3.5" above the manifold with a taller phenolic spacer and it evened out cylinder distribution due to better atomization and airflow through the runners immediately after the baseplate. Helped my top end too by 400 rpm. Just another thought. Keep being AWESOME, UT!!!

[@wakjob961]

Running a 1" spacer... on top of the 2BBL conversion adapter which is a solid 1-1/2" above the manifold on my 200cid Ford LOG head...Weber carbs are a special breed for sure. Got the tricked out 32/36 to run great... the 38/38 is giving me a fight... but I'll win ;-)

[@alexlandsberger1423]

Did that same thing on a Ford 2.3 EFI when I converted it to carb ran really good I just used a oem Holley 2bbl 360 carb and decreased the jet size by 40%

[@shawnbroyles8274]

I thought that would help!

[@pookysdad4884]

A poor man's tunnel ram!

[@Marco-lv8co]

I built a Nissan 240z engine 25years ago, it had 10:1 comp, i blueprinted the engine, do not Remember what cam. I put on 3 weber dohc 45. It made 188 rw hp, at the rolling dyno. The intake sound of those webers, gave me the chills. I had a garage in Stockholm, at that time, and worked on both Porsches and Ferraris, and american cars. My heart was allways on us cars.

[@ShadeTreeKennyT]

I never knew you could mix spark plug heat ranges on an engine, or run different size jets on the same carb. It makes sense after you broke it down. Thanks for the knowledge yet again UT!

[@davidleonard8369]

He'll, we used to run different valve lash on half of the cylinders to try to get a broader torque curve.

[@luisgonzalez8423]

Almost every carb have different size jets and meters you can swap out for preformance or economy

[@i3rent2043]

Guys would run different heat plugs on old air cooled 3 cylinder motorcycles bc the middle cylinder usually runs hotter

[@jamesblair9614]

I’ve run the same intake on a street car, and I suspected there was strange fuel distribution at part throttle, but I never did your plug trick, and I’m stunned at the variation between cylinders. The car is long gone, but I still have all the hot parts, incase the bug bites again.

[@tx9cuda]

I love that you walk us through the process and the cause and effect. Great video!

[@damonpodulka492]

Ran inline Chevy six for years. You need to try a 2 inch carb spacer to increase the plenum for better distribution. Also, the unequal length runners are part of the issue. The signal back to the carb is stronger for your two end cylinders and they are drawing more air/fuel. Have done work with diverters and grinding to try to even out the fuel distribution on the Chevys. For a Chevy 6 the number 5 cylinder was usually the piston to fail as the firing order and intake configuration caused that cylinder to run leanest. Good luck and thanks for these videos.

[@UncleTonysGarage]

Spacer tuning is planned once our true baseline is established

[@davidleonard8369]

@@UncleTonysGarage one thing at a time, grasshopper.

[@gordross4726]

Having not worked on cars (but wish I had), I find it fascinating the knowledge needed to make a car run fast. Thanks so much Uncle Tony for all the info; really enjoy your channel.

[@DrShankenstein]

Thank you Uncle Tony! As always this was very informative.

[@johnelliott7375]

#350 and a hour ago my bell is slacking lately. I love these tuning videos! Thanks for your time Uncle Tony! Good evening and I hope you have a great weekend! TTYL

[@Sedan57Chevy]

It was so thoughtful of Chrysler Corp to leave a useful little work service between the hood opening and the edge of the fender! Great info here Tony.

[@moparmatt5896]

I had an ongoing study of those with a buddy years ago we did some tuning with one and it really dropped my jaw to see and feel how much torque they make i fell in love with that engine

[@JacksonEngineering]

I learned at least two things! Maybe more! Thanks Uncle Tony!

[@WARD5KUSTOMZ]

Thank you your videos. The efi system on my F150 died. Changed it over to carb and hei. Got it timed correctly and the carb tuning perfectly. Running way better and way more efficient than the efi system that was on it from factory. Way more power and 23mpg.

[@josecuevas8602]

Tony you should consider a smaller carburetor and mount turn it 90°, in form that the front of the carburetor is pointing toward the left [fender] side. The reason for my madness is that turning it 90° is for better fuel distribution. Having the carburetor turned 90° will provide you with one idle circuit feeding the rear 3 cylinders and the other idle circuit feeding the front 3 cylinder. Furthermore, when an engine has an carburetor of greater CFM [size] than the engine can handle it becomes harder for the fuel to be pulled out of the boosters, due to the that the vaccum signal needed to pull the fuel is not enough. It is actually the opposite direction that is needed. In other words a larger jet is need to compensate for the week vaccum signal. Or go with a smaller carburetor, Holley and Edelbrock bought manufacture 500 CFM 4 bbl. Carburetors. Holley even makes a 500 CFM 2bbl. Unless you're planning to Rev. 8000 rpm a 650 cfm is to large. especially if your tuning goal is for torque. No matter the outcome I will still be a fan of your channel .

[@dtiger8317]

You got it right Holly 500 2 barrel Should work very well

[@thedodong4268]

Thanks for this content UTG I really enjoy following all you project this is AWESOME!!!

[@johnelliott7375]

We got something but it is only a first step of many in a series of steps to optimize the set up you need for a close as your going to get to a perfect tune on the motor you have designed the parts list and built for a specific purpose/use/reason. God bless, good evening and great weekend to you all. Enjoy, I did back to my analog thinking till I get back to the 7-5:30. Thanks for the update and a lesson of many.

[@chrisfarrugia5397]

Thanks so Much Tony !!!! I have half my cylinders running lean and yes it corresponds to the low lying cylinders on my manifold........ ahhhhh what a great video !!

[@robertmedsker5305]

Nice video I like how you basically explain how YOUR THE COMPUTER .. that's how it's done old school masters..

[@forrestcowan448]

One of the best videos you've ever done imo

[@AllTheBoost]

I’ve been asking for a video like this for 10 years. Us young guys thank you sir

[@phongnguyen007]

Worth a subscription. As i love carburetor also, the mechanical way of life is like analog

[@Mynextproject_74]

That was great information! I am doing the same with my 318 Duster. It's a temporary engine but I want it to run as hard as it can!

[@motomichael4775]

This was a great video Tony! I dig the engine fuel distribution characteristics diagnosis/analysis topic.

[@AimlessMoto]

I run a 570 Street Avenger on my 289... 58 primaries, 62 secondaries... I have jets from 60 down to 50. They're readily available on Amazon.

[@chrishensley6745]

True grass roots right there Tony......Love your channel!

[@JMTiedemann]

Great video! Thanks uncle Tony!

[@suzyjohnson4667]

Thanks uncle Tony. Learned something indeed!

[@obsessedwithcars219]

Thank you uncle tony!

[@Ramas1z1]

I have to give Kudo to Tony for all that he does on this channel. I would also like to say I'm nowhere near the mechanic that Tony happens to be. I cringe about how much I've forgotten compared to what I have retained. Yikes! All of that being said, I would like to offer up as something that is not attacking what he says, but "in addition to" what he has said about the Slant 6. Because of the manifold design, the slant has problems with the end cylinders' A/F. Way back in the day, I was member of the Slant6 club of America and someone in the club had (long before I joined) helped to minimize that problem with a 4 barrel carb. They would weld in a plate which separated/split the manifold to 3 plenums on each side. They then rotated the carb 90 degrees so each "side" of the manifiold would have a primary and secondary to feed it. My experience was seat of the pants in the cars, but they seems to have better throttle response and a bit more power. I never heard a owner that had done that modification to be unhappy with the results. He says at 9:55 "that this is an perfect example of where port fuel injection would be far superior to a carbureted setup." I have always wanted to spend some time and do that to a Slant but never had the time/money/car. That always seemed to be a solution to me. Thanks again Tony!

[@chrissanders2562]

This video also applies to chevette engines as they have the same intake setup. Thanks! I have learned alot from you.

[@jimjungle1397]

With most 650 double pumpers (List 4777) the jets start off at 67 front and 73 rear. The power valve in that carb with original metering block is about the difference with these, or maybe 6 jet sizes. Maybe slightly less. The stock jetting at sea level is often about 5% rich. Higher altitude, the same jets would be even richer. With 6 cylinder engines at the circle track, some V8 rules don't always apply.

[@chrishensley6745]

Great video...like you said Tony on the fuel part going to the cylinders.....was the Draw back on the old straight 8 Buicks back in the early 50,s on the end cylinders running lean.Thank you for this great channel.

[@vtwinaddicted5852]

Throwing down the knowledge Tony!!!

[@kevintyler7614]

Well done Tony

[@zachdickson8267]

Goddamn I learn so much every time I watch your lecture vids. You the man uncle Tony!!

[@lessharratt8719]

Great tutorial Tony.

[@axipixel5811]

Now it's starting to make a lot of sense why a lot of straight sixes got made with two carbs.

[@Cstoreri]

Thanks UTG

[@cheatingiscompeting3647]

Take notes from this man. A person with this much knowledge don't come around to often.

[@YoureGonnaNeedABiggerBoat]

Keep fighting the good fight on my 6 cylinders with Offenhauser manifold and Edelbrock carburetors but I run the carbs sideways front pointed a fender. One of these days I want to see a hillside Hemi in a boat.

[@livewire2759]

Yes. Turn the carb sideways, keep it simple. That'll even everything out without having to run different plugs in different cylinders or different jets for different barrels.

[@jonvon9250]

Yes I tried to run the carb from the back the first time on my six and then I turned it sideways and it liked it a lot better

[@speedy_pit_stop]

I thought you were going for the intake, but you surprised me again. I can't wait to see the results after the changes you talked about.

[@madgamer0001]

I have a 1985 dodge D 100 with the slant Has a Holley 1 bb. It’s doing the exact same thing one and six are running kind of dark. And so on. I’m running NGK spark plugs in mine. The engines totally stock inside and the only thing I’ve done to it is put in a high dollar coil. It runs really good but it’s got the carburetor that you can’t adjust the idle mixture . Changing the heat range on two plugs makes sense to me. Never thought about that.

[@jimbo682]

Great Vid Tony! Lots of Knowledge there. I would love to see a sidexside comparison with what you have done with naturally aspirated VS Holley EfI Sniper Master Kit. Keep up the Great work

[@NITROUSnBIASPLYS]

Where’s the shop cat?! 🐈

[@brianfloyd5510]

Great vid UT!!

[@frogman8591]

Nice Speed Secrets Tony, thanks.

[@jeremypike9153]

Thank you Tony

[@victormiranda9163]

the guy for Oz saying that 3 SU carbs is the ticket... ya may want to consider that carburetor option. now to google used SU carbs

[@moparmatt5896]

Awsome thats a need to know for anyone who loves the slant six and wants to tune it for power

[@phillipleeds296]

Really interesting stuff, thank you.

[@tomnekuda3818]

Really a good, common sense approach to engine tuning. If I remember correctly(set me straight if I'm wrong) Chevy used a couple of methods on some of their big blocks to equalize the cylinder efficiency: 1) stagger jetting of some engines. 2) "twisting" the carb/manifold so it sat on an angle on top the engine to try to equalize runner length. 3) A combination of 1&2 above. If I remember correctly, it worked quite well for them.

[@richardcranium5839]

runner length difference is part of what made the slant 6 so damn smooth. you basically had a lag on 1 and 6 so accelerating was like running a 4 cylinder and having 2 more kick in. if you paid attention you could feel it.

[@mongomay1]

Thank you for tuning in with video Tony!

[@woobydoocat]

Awesome wealth of knowledge.

[@CRay-yq8se]

So much knowledge!! I grew up every vehicle I owned was TBI or EFI...I now have a 4x4 79 SWB with a 2 bolt main SB 400... highly considering swapping to EFI, as its hard to start and every now and then, it will starve of fuel when driving and die....it starts right back up, so I don't think it is fluiding the carb.... watched a video of Uncle Tony complaining about an issue on Ram Charger he went ahead and swapped back to carb...so here I go, I'll watch and read some more on proper tuning ect...see if I can get it reliable before spending the $1700 on a conversion kit.

[@Fun-under-the-hood]

love all the lightning holes everywhere! ❤❤❤ looks cool. whent kind of crazy on that shock tower😂 hopefully didn't hurt the strength of it. love it!!!

[@donaldisrael7147]

That Dart behind you reminded me of my sr. year of high school. A good friend got a 64 Dart 2 dr. ht 225 4speed for graduation.

[@moparmatt5896]

On another thought. so many guys just dont even know what the slant six is capable of. Many of us over looked it,just because it wasnt a v8. Then i discovered Doug Dutra. and followed some of his work.wich led me to play with one for myself and had a blast doing it. O would love to have with one with a turbo and port fuel injection

[@richardpriestly3499]

Hey Uncle Tony, My son and I have been developing a Slant Six in an Aussie VC Valiant (1966). We have a 465 vac Holley and we found the same thing, fuel distribution was all over the place. Thanks for the vid, I’d never seen the clean plugs method to assess, we had used a twin extractor exhaust with oxygen sensors but that only told us front 3 vs rear 3. Your plug method is VERY useful. Just for info Aussie Speed make a long runner manifold for the slant six that mounts a Holley 4bbl in an East West configuration. We invested in that to fix the front rear balance but it doesn’t tell us individual cylinders. Also I had never considered jetting differently on the same bowl (L to R) on yours but that probably won’t be effective with an East West manifold

[@kristopherdavis4764]

I've seen this on Ford 300 inline sixes. What I've done to help this is to clock the carburetor 90 degrees. It helps with fuel distribution.

[@davidedward6516]

Excellent video! Would definitely appreciate more plug reading and tuning videos

[@ferrofilos]

my dad used to drill a little starting hole mark on the drillpress on each sparkplug to identify the cilinder of wich was put in and then out to check them and dont mixthem when put it back on the engine, he drill the 3 cilinder sparkplug 3 holes on the side of the nut part on the side.

[@vitaminc1071]

Uncle Tony I strongly recommend reading DV's book on super tuning Holley carbs. Couple things, not necessarily echoing DV here: 1) a "large" carb spacer (like a 2" open deal) might help your distribution problem a lot - gives some distance for mixing and dynamics to take effect. Might be worth a try. 2) power valve will only take effect when vacuum is very low, so if not WOT under load the power valve may as well be blocked (I know you know this). 3) I am guessing that lower displacement machine would like a leaner relationship between the idle feed restrictors and idle air bleeds, I.e. air corrector jets. 4) slap an O2 sensor on there. It's not cheating. It's good clean science! Keep the content rolling, man! Nice job!

[@garypapesh1345]

Solid gold 💯👍

[@westcoastdodge]

That motor is screaming for a set of weber dcoe or dellorto style side draught carburettors,would think that would sort any mixture issues(providing you could find/make the intake manifold) great job Tony 👌

[@livewire2759]

He can use the same manifold and carb and get much better distribution if he just turns the carb 90 degrees. That will line up both the primary and secondary barrels with the center of the intake runners for more even distribution.

[@matsumoto9244]

I was thinking the same. With the Weber DCOE style carb you could fabricate equal length intake runners. I would think the setup would allow more precise tuning for each pair of cylinders. Perfect match for those that love carbs.

[@v6ileib]

@@matsumoto9244 Yes. And it would be possible to make the total intake runner length exactly right for this engine.

[@johnelliott7375]

I love the looks of your motor, I think I need a old manual truck with a 9.5 -1 slant hemi. Back to the video.

[@Titan-uy1qy]

Thank you sir!

[@Chubbycat747]

Great vid.

[@sterlingbeck5247]

Good stuff!

[@brienduarte1015]

I completely understand your formula for the Dart. I understand why you want to use the carburetor too. I would love to see what you can do with a fabricated manifold with straight ports and 6 individual fuel injectors.

[@ricjona1069]

Make 3 separate 2 barrel, 2 cylinder manifolds. Set each up with a 2 barrel synchronized carb like a Weber 38/38 or progressive 36/32 then tie each pair of contiguous manifolds together with a balance tube, similar to the old Man-A-Fre intakes made for the gm inlines. You can also tune the runner length if you do that.

[@davidwinters4762]

Custom make baffles that go under the carb to help distribution. But the different runners changes the torqu curve. the outer runners help low end the inner 4 help top end.

[@sydneychase780]

Lee Marshall has the right idea, tall 2"+ spacer, clock carb to put primary towards the valve cover. I ran 2 giant twin "H" carbs on my 235 Chevy Fenton dual intake 3" above log Runner, 3" straight stack on carbs because fuel standoff @ WOT. ISKY CAM that Ed told me would break stuff, driveline actually. 11:36 @ 91 in the 1/4 mi. YOU CAN DO THIS!!

[@georgebonney90]

Thank you sir 👍

[@nickbonvino]

He’s a living, breathing encyclopedia of car knowledge

[@oikkuoek]

I would still ditch that intake and weld something with triple Strömbergs.. Although you COULD trick that 4-brl to somewhat even fuel distribution, with tiny jets and clocking the body, it would still run poorly compared to three separate carbs. Even the OG fume accumulator would work better multiplied by three than that single holley.

[@thefixmdude22512]

Great explanation. Would plug indexing do much?

[@louisfugazi3991]

Uncle Tony this is helpful. I'm at the point on my motor where I'm tuning my Ford 200. It has 3 carbs, with the main carb in the middle and progressive linkage on the two outer carbs. I just got the 3 carbs to idle and I was thinking how am I going to get this in the ball park(or close) on the main jetting. I can't drive it yet because I'm rebuilding the entire braking system. Man I could use some helpful hints from you with that. Having a real hard time getting the hard lines not to leak. Great job on these videos.

[@abarguy]

I’m sorry, Tony, but I really don’t agree with changing heat ranges on #1 and #6 plugs. All that does it attempt to hide a future plug diagnosis. You need to fix the actual fuel distribution issue. Look at rotating the carb 90 degrees, putting the primary side towards the driver fender. This will at least give a good distribution in the primary side of the carb. I think, using the manifold you have limits proper primary and secondary distribution, unfortunately. A longer runner manifold like the old Hyper pac manifold or the 4 bbl version of the Aussi manifold would serve you way better than what you have. Doug Dutra worked long and hard fixing the fuel distribution in the HyperPac manifold he designed for Clifford and was probably the best one available for a slant.

[@shoominati23]

Another way to do a good plug chop is to get the engine good and warm at the bottom of a steep hill, swap over to a fresh set of plugs and run the car hard up the hill for at least 20 seconds before shutting off and coasting over to the side .. done this alot tuning 2 stroke motorcycles .. You've got to read the band on the side of the porcelain to get the correct reading by the way, not just the electrode, thats why you saw people like grumpy and smokey at the track examining their plugs with their magnifying lights

[@Rembrant65]

Hey! That's only half of a video. Did the hotter plugs fix the issue? Tune in tomorrow to see if our hero saves the girl! You better do the follow up!

[@twistedturbotwistedturbo]

I take offense to the dig on Champion spark plugs. I've got many many fine running lawn mowers using their plugs, and none have fuel distributions woes, lol. Love the content Uncle Tony!

[@brucew13]

Awesome! Hanging out real bad for the next installment! I love it when Tony's just goes over the basics and makes it simple as! I dunno if I went the correct way but I installed an O2 gauge in one bank of my exhaust and its tuned with that, just did the exactly same on the other side of carb :) What would be really cool if Tony got one of those e bay $140 Bosch sensors and a gauge and seen how it reads compared to the plug tune method. Anyone agree?

[@UncleTonysGarage]

Single O2 won't tell you the distribution. You would need individual EGTs in each primary tube for that information

[@Mike_Collins392]

Ruster probably has some hidden trick electronics. He is at his shop downloading sensor info into a rack of computers working their ass off , crunching numbers from from millisecond atmospheric changes as well as positive and negative changes in the engine at every change in RPM. It all probably ends up at a line of glass tubes and vials mixing exotic chemicals like hydrazine and phosphorous chloride calculating and mixing an additive for his next outing , based on his current tune as well as the altitude and expected weather conditions.

[@brucew13]

@@UncleTonysGarage arrr yes never thought about that, great series, love this stuff! Thanks Bruce from NZ

[@AndrewHemstreet]

A hotter plug won't change the mixture to those cylinders. If changing the left jets doesn't change those cylinders, I wonder if you could get some really fine wire to be in the air path to the end cylinders to get fuel to attach and route into the middle, kinda like how when I wash my hair water runs down my arm and runs off my elbow.

[@jontrudell7529]

CULT LEADER UTG!!!

[@Z_732]

Good job explaining. Your exactly right. Just remind people to limit their changes they make so they can learn what the engine specifically wants. Too many changes at once can be counteracting.. for your situation, I dont think it unreasonable to change carb and plugs. Like you said, you ran the engine for a bit and got it to temp before pulling the plugs. So you are doing it one at a time. However. It sounds like you didn't really hit it hard.. that can make a difference as well. Like you said again. . Reading plugs immediately after a run can answer all that. So your basic tune-up for now is based basically on no load, but could be completely different after a pull. Very good stuff UT.. I just wanted to make a statement that the best way is one change at a time. (Like you are doing exactly) seems like a lot of people get in a hurry and change too many things. Just wanted to remind people.

[@ericdanielson1138]

Once you found the right plug you can tune each cyl with gap as well . Although Minimal it can be usefull. Also as Mentioned below turn the carb sideways with a open spacer. JMHO .

[@Buzzard-wq1bw]

Dam I wish a triple Weber set up for this engine wasn’t so expensive, this car could really take advantage!

[@garielgrenadius7564]

Excellent video. Real motor talk from a real motorhead. We just put dual Webers on a slant 6 to equal out the mixture across the cylinders. It's a split manifold with an equalizer tube. I am curious why you went with a single carb instead of a dually setup.

[@NathansMoparGarage]

All the little details add up

[@donwest259]

turn the carb 90 deg so the primaries are furthest from motor as possible. had a built chevy 6 cyl years ago with a clifford 4bbl and holley and that seemed to help distribution on that motor

[@johnk3386]

Another awesome video! Very informative! How would a open carb spacer cocked at °45 effect the distribution? And would it have +/- effect on top end power? Could you port and epoxy manifold to improve flow characteristics?

[@bodgiesteve8849]

Tripple DCOE Webbers, on a ram manifold are your answer. look , work, and sound fantastic. also an art to tune, but once you ret it right, results are very satisfying. Tripple SU carbs would also work

[@jim55282]

A dual carb split intake ( 3 into 1 x2 ) is a potential solution. They are short runner designs so it wouldn't hurt your top end. Plus, 2 carbs is twice as much fun. Hyperpack intake has the best distribution but the long runner "might" limit top end. It also might help low and midrange. Could the stock intake be ported or to increase flow to the center runners or could the long runners be modified for restriction?