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Weber Carb Tuning?

Off Topic Discussion

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Just curious if anyone here has any experience with tuning weber carbies?

In particular im abit confused regarding the Air corrector jets... Im sure it applies to all webers but the one in question is a 32/36... Everywhere ive read says the air corrector jet has more sway over the AFR at higher rpm's... Ive done a few cars with 32/36's now and they seem to lean out a little in the top end but If I use a smaller air corrector jet then it makes the AFR richer throughout the whole rev range evenly during a dyno pull...

I think you might have accidentally gotten lost and you're on the wrong forum? ;)

I for one definitely can't offer any useful advice sorry.

You should sort out both main jet and air correction jet, while AFR would be acceptable through the whole rev range or you can`t improve it anymore. But remember that you can`t make it ideal as with EFI.

If you pick up a smaller air correction jet and it makes AFR rich through the whole rev range try to install a smaller main jet

BTW, how much the starting configuration leaning out in the top end?

Haha Webers can be high performance Andre :P maybe you shoulda called it EFI Performance Academy, JoKeS

Truth is I dont know anyone with carby knowledge or even any forums, so stuck it in off topic hoping someone one here might know.

from memory (on a different laptop to the one with my notes) I had 160main jets and 170 Air correctors... and was 13:1 until around 4000rpm then would lean out to around 13.8:1 by 5500rpm... Every manual/website ive read says air correctors mainly effect top end... cool so I fit 150 air correctors hoping just the top end would be effected but ended up with 12.2:1 until 4000rpm and leaning out to 13.0:1 (pretty much exact same fuel curve just richer across the board)

So dropped down to 150 mains and ended up with 12.5:1 and leans out to 13.5:1 in the top end which I accepted... But would like to know how to stop the top end leaning out.

Even if no one knows the answer maybe you could point me towards a carby or even better weber specific forum?

The answer is - you can`t. Carburetor doesn`t have flexibility for that. CFM of the engine is very unlinear, so that the calibrated jet can`t provide enough fuel on the top end, you could try to fit another carburetor (holley 4 cam for example) to increase the capability to work with unlinear CFM. That`s why carburetion is not finded on modern engines. It`s like a turbocharger, you can`t sort out the turbo that is same good in low and high rpm, bi-turbo and twin turbo solutions solve that problem.

Auto manufacturers were engaged in masochism with improving carburetion cars in the eighties. Look at EPC of Toyota Sprinter Carib AL25 with 3ASU engine. 2 carburetors and INSANE vacuum distribution diagram)