Weber Tuning

[ack fia]

I found a combination of jets and adjustments that work great on my little 302. It has 48 IDA's with 37mm chokes. The jets and adjustments that work well for me and eliminate the annoying stumble at 2000 RPM are:
Idle jet - 65
Idle air corrector - 120
Main fuel jet - 150
Air corrector - 200
E tube - F7
Accel Jet - 50
Accel bypass - 50
Idle needle valves approx. 7/8
At first I was hesitant to go to 65 on the idle jet (small motor) but reading the Weber manual indicated to me that the jet only makes more fuel available to the needle setting so I gave it a try and the stumble at transition disappeared.
Pat is now a happy camper.

[ToyCollector]

Thanks for posting. I posted mine recently as well for a 289 HiPo and you will find many of those that post are very close in their settings.

[Cal Metal]

ack fia:

Explain your "accelerator jet" and thanks for the data. Everyone is always looking for solutions with Webers. The big question might be: what are the specs on your cam?

[ack fia]

I guess you would more accurately call these the Accelerator pump orifice and the pump bypass jet.
The cam in the 302 is mild hydraulic with unknown overlap. I won't know more till I take the engine apart.

[nanard289]

Originally posted by ack fia


It has 48 IDA's with 37mm chokes.

Thanks for your information but it should be for a street use only! For Hi Perf engine (that is the purpose of Weber induction) , several engine builders use 40 or 42mm chokes for a 302cid