BACKFIRE PROBLEM!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
03-25-2009, 12:02 AM
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Car: 1985 Z28
Transmission: T5
BACKFIRE PROBLEM!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Hey everybody...
I've been having a backfire problem lately. I have an 1985 Z28, LG4 305, Vortec heads, and a 600CFM Edelbrock carburator which is brand new. Since I've changed the carb, it runs good, it accelerates great, and the idol is smooth. But, if during accelerating, I rev it until 4000rpm (as an example), and immidiately let go of the gas to let the car deaccelerate by itself...the car backfires like crazy.
Is this a sign that the engine is running rich??? If so, what size of rods and jets is adequate for my application????
Thank you for the cooperation!!!!!!!!!!
Jon
I've been having a backfire problem lately. I have an 1985 Z28, LG4 305, Vortec heads, and a 600CFM Edelbrock carburator which is brand new. Since I've changed the carb, it runs good, it accelerates great, and the idol is smooth. But, if during accelerating, I rev it until 4000rpm (as an example), and immidiately let go of the gas to let the car deaccelerate by itself...the car backfires like crazy.
Is this a sign that the engine is running rich??? If so, what size of rods and jets is adequate for my application????
Thank you for the cooperation!!!!!!!!!!
Jon
03-25-2009, 11:43 AM
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
It's a sign your idle mixture is too rich.
When the throttle is closed, air and fuel are being metered by the idle system, not the rods & jets.
When the throttle is closed, air and fuel are being metered by the idle system, not the rods & jets.
03-25-2009, 08:26 PM
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Car: 1985 Z28
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