350 Engine Sound

Hey guys, New guy here. Been working on old cars for several years(ASE Certified) I have a question. I just bought a 78 camaro LT with 350/350 combo. starts up great, great idle, and runs good except when it ie opened up. When I get onto it it starts backfireing through the carb. The car is mostly original. I have already put a new Edlebrock carb and intake combo and a new Accel Blueprint HEI distributor. The ingition timing is right on an so is the air/fuel ratio and idle. Any ideas? Also, Does anyone know a site that I can research some engine and head casting numbers?
Thanks,

Thanks Streets. I was thinking it was a valve sticking or bent.

i had a 350 do the same thing and it was a worn cam shaft.

Does the car have any exhaust restriction? Had a buddy one time that had a 73 Laguna and did the same thing . Come to find out the tailpipes were double walled and the inner pipe had collapsed. If it's not that I tend to agree with Street's ,maybe bad valve guide's also.Does the Camaro smoke at all or consume any oil?

Look into the lifters too. If one is not compressing properly due to age/oil problems/grit, it will cause the valves to stay open to long.

sounds like you might have a flat cam, that is a cam with the lobes worn down.:(