(Login davidn3) Member from IP address 126.96.36.199
Here is what I have. (chevy 350)- Sorry but I can't find a chevy forum with guys that are knowledgeable in tuning.
I put a new cam in it (comp cam 262xe) and lifters to match. New carb (quick fuel 580) And MSD dizzy and 6al box.
I have timing set at 17 initial and 38 total all in at about 3200RPM. It seems to be running great and smooth with throttle response and idle. When I spike the throttle at Idle it backfires in the carb. If I do a short throttle spike, it does ok. Its only when I floor it and hold it there. It has a 35 shooter in it. Changed from a 31, with no change. The accelerator pump is responding fine. I've adjusted the valves a couple of times. It runs great at any RPM so I think it is a fuel issue. Any thoughts? I'm out of things to check. Maybe a higher PV? I'm running about 10" vac at idle with a 6.5PV. But it doesn't pop until vac is zero, so I don't think a PV would make difference.