Weber 32/36 conversion / Q? need to re-jet?? (1 Viewer)

Dizzy

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Without an O2 sensor, and probably a heated one with headers, you could measure your MPG, and post up pics of the spark plugs. Hiccup is lean, exhaust pop is unburnt fuel.
 
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It isn’t clear why you would think that the carb was “flooding” the engine. The symptoms are consistent with a lean condition and the circumstances, like a wide open throttle with no choke applied are inconsistent with flooding.
Ok thx for input.
Advancing timing from 7degree BTDC to 11-12 BTDC (with no further carb adjustments), seems to have solved the faltering,stuttering, backfiring at wide open throttle issue. Q? is that consistent with a lean fuel condition?
Open for other suggestions pls, as I don’t think my problem is completely solved.
 
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Without an O2 sensor, and probably a heated one with headers, you could measure your MPG, and post up pics of the spark plugs. Hiccup is lean, exhaust pop is unburnt fuel.
Thx. Planning on driving for a tank of gas and then pulling plugs. Unable to measure mpg as speedo is having conniptions ( squealing like stuck pig) and is on the bench for a good talking to!
 
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Q? is that consistent with a lean fuel condition?
Open for other suggestions pls, as I don’t think my problem is completely solved.

No. If the power drops off with increasing RPM, then that would be consistent with a sticking centrifugal advance that could be partially compensated by advancing it a little, but the rest of the symptoms are consistent with a lean mixture.
 

Dizzy

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I'd jet the carb richer, like Pin_Head said. However, it would be really important to know first that the motor is pulling more than 15in/Hg of vacuum at the manifold, and that the spark plugs look clean and are gapped properly.

One of the big differences between the Weber and the Aisan is that I've noticed that the Aisan can have a generous opening on the idle mix screw. On the Weber, the folks at Pierce Manifolds, Weber Redline, etc, suggest no more than 1.5 turn out on the idle mix screw. They suggest this because if the hole that runs the idle circuit is drawing all the fuel mix from the idle circuit, then it starves the next progression hole. At very least, your idle jet is probably a bit lean.
 

flee

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Another thing to keep in mind is that the Weber manual says to limit fuel pressure to 4 psi or less.
The F's mechanical fuel pump puts out more than that so a pressure regulator is a good idea.
 

Hugh Heifer

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When I initially read the OP I immediately thought a vacuum leak at the base of the carb where the adapter is.
I will add I also ran a fuel pressure regulator on my 2F when I had a Weber.
Had lots of vacuum issues and changed to a Troll Hole carb and non-USA dizzy and Petronix.
 

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