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
*MERCHANDISE:
*SOCIAL MEDIA:

[donjohnston]

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.

[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.

[bigbear]

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.

[leemarshall]

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.

[andyreiwitch]

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!!!

[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!

[txcuda]

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

[SedanChevy]

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.

[johnelliott]

#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

[UnityMotorSportsGarage]

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

[gordross]

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.

[damonpodulka]

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.

[Marco-lvco]

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.

[jamesblair]

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.

[moparmatt]

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

[DrShankenstein]

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

[chrisfarrugia]

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

[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

[johnelliott]

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.

[AllTheBoost]

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