Carb jetting
Carb jetting
(OP)
After drag racing several different cars for over 25 years I am still stumped with carb jetting. I have tried the new weather station computers and they just don't seem to work for my car. Coming up with an adjusted altitude based on temperature, humidity, and barometer and using it to pridict performance just doesn't work. Seems like barometer has the most effect on performance. I am running a 12 to 1 compression 383 chevy smallblock that runs 10.70 to 10.90. When the weather station says the air is worse(higher altitude reading) I would think my exhaust temp would go down, but it goes up. Any ideas?





RE: Carb jetting
I'd recommend you first dial in the AFR, then fine tune with spark timing. Spark timing can and should be advanced to compensate for lower barometric pressure or higher humidity, at a constant AFR.
RE: Carb jetting
RE: Carb jetting
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