need help please! backfiring and popping
#1
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Car: 89 formula/00 z28
Engine: carbed 350/ls1
Transmission: 700r4/ a4
Axle/Gears: 3.23 posi/ 3.73 posi
need help please! backfiring and popping
just got done with my cam change and car is popping threw carb and skipping. it idle fine but when u get on it going down the road it backfires and miss and pops. i set timing and adjusted it no help , re adjusted preload form 1/2 to 1/4 no help, changed carb no help. checked wires 18436572. what could it be? im thinking maybe fouled plugs. had that pop before. please help!!!
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Car: 1988 Firebird Formula
Engine: 5.7 TPI
Transmission: 700r4
Axle/Gears: 3.27 posi 9 bolt
Re: need help please! backfiring and popping
Only thing I can think of is the ignition timing is off. In order for it to backfire back through the carb your spark timimg is way too early. Did you remove the distibuter?. throw a timing light on it and see if it's correct at idle and when you raise the engine speed.
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Car: 1984 Camaro Z28
Engine: 350ci
Transmission: 700r4
Axle/Gears: 3.31 non posi = no traction
Re: need help please! backfiring and popping
I agree. Has to be timing.
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Car: 86 T/A, 83 Z/28
Engine: 5.0 TPI, 350 2 X 4 bbl
Transmission: 4 speed auto, 5 speed manual
Axle/Gears: 3.23 posi, 3.73 std
Re: need help please! backfiring and popping
To my knowledge there are 2 primary causes of backfires in the intake. 1 is timing which is most likely and 2 is a lean mixture. Check for vacuum leaks. Now your saying you had this popping before the cam swap so its the same as it was before correct? Or am i missreading that?
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Car: 1984 Camaro Z28
Engine: 350ci
Transmission: 700r4
Axle/Gears: 3.31 non posi = no traction
Re: need help please! backfiring and popping
I would pull the distributor back out and reinstall it. could be in wrong. I once had this problem, pulled it, put it back in, adjusted timing, fixed it.
#6
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Car: 89 formula/00 z28
Engine: carbed 350/ls1
Transmission: 700r4/ a4
Axle/Gears: 3.23 posi/ 3.73 posi
Re: need help please! backfiring and popping
Only thing I can think of is the ignition timing is off. In order for it to backfire back through the carb your spark timimg is way too early. Did you remove the distibuter?. throw a timing light on it and see if it's correct at idle and when you raise the engine speed.
#7
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Car: 89 formula/00 z28
Engine: carbed 350/ls1
Transmission: 700r4/ a4
Axle/Gears: 3.23 posi/ 3.73 posi
Re: need help please! backfiring and popping
To my knowledge there are 2 primary causes of backfires in the intake. 1 is timing which is most likely and 2 is a lean mixture. Check for vacuum leaks. Now your saying you had this popping before the cam swap so its the same as it was before correct? Or am i missreading that?
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Car: 1982 Camaro z-28
Engine: 307
Transmission: th-350 with stage 2 shift kit
Axle/Gears: stock
Re: need help please! backfiring and popping
To my knowledge there are 2 primary causes of backfires in the intake. 1 is timing which is most likely and 2 is a lean mixture. Check for vacuum leaks. Now your saying you had this popping before the cam swap so its the same as it was before correct? Or am i missreading that?
#11
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Car: 89 formula/00 z28
Engine: carbed 350/ls1
Transmission: 700r4/ a4
Axle/Gears: 3.23 posi/ 3.73 posi
Re: need help please! backfiring and popping
well car wont run with timing set at 10. got new plugs no change. set preload to 1/8 some what better not popping that bad now. i think i may try 1/16 see what it does. what yall think?
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