cmg1

ANy suggestions on how to fix.

1973 stock 350, new carb, maybe vacuum lines crossed?

engined timed, dwell correct, sometimes cuts out when pedle pushed to floor.

any help appreciated.

A C

Is is backfiring through the intake, or exhaust? :confused:

AC

cmg1

backfiring is through exhaust.

Scott78

Double check that the mark on the balancer is the same as TDC, I've had balancers slip and the mark be way off. If thats correct and timing is setup right either extra fuel in the exhaust or a exhaust valve or valve spring. But either the valve or spring should be making a noise I would think if they were bad.
Scott

MotorHead

I had a backfire problem when I forst bought mine, thought it was kinda cool
when I let my foot off the gas, but got kinda annoying. Rebuilt the carb and it went away :D

Jughead

Could be running too rich...unspent gas vapors in exhaust pipes igniting??

Red73

Nachos and beer....oh sorry, wrong tailpipe? :D

MotorHead

1970 Stingray, was actually thinking of your sig pic when I took mine, looks like
I'm gonna have to get down lower next time :D

vettedan

Dittos to scott78- also, use timing light on each plug wire to verify you don't have a misfire going on. Usually backfire is timing of misfire.
Dan

clem zahrobsky

a bad diversion valve on the air pump or air leaks in the exhaust system will cause backfiring. :chevy

Jughead

Yeah you gotta get down low with the worms. :D


And, I want to change my answer to what Clem said. :lol: He should know. :yesnod: