Quote Originally Posted by TUBJUB
When I drive my car (350, stock dished pistons on a stock bottom end, RPM Air-Gap intake, 750 holley, vortec heads, msd ignition, comp 268XE cam, 1/2 fuel line with a holley black fuel pump 150ish GPH) on the street, just cruising, i hear and feel a pop or backfire. Under acceleration it works fine. When we built the engine we didn't have it bored, just re-ringed and the top end is completely new except the carb. It is the second carb we put on it. We got this one from a race shop we go to and they both said it was a perfectly good carb when the gave it to use. I know a 750 is alittle big but would that make it pop? is there something that makes it pop that I'm not seeing? I don't really know what to ask, I guess just looking for some suggestions on what to check.
HI,
I HAD THE SAME PROBLEM AND WHAT HAPPENED TO ME WAS MY CAM LOBES WORE AND CAUSING THE VALVES NOT TO OPEN AND CLOSE PROPERLY...ALSO MAKE SURE YOU GOT THE VALVES ALL ADJUSTED PROPERLY!!!!HOPE THIS HELPS OUT!