wilsonhvac
Jul 11th, 04, 10:54 PM
Hi, Looking for some advice, I recently rebuilt a 350 chevy motor complete with pistons,cam lifters new intake, edelbrock 600 carb hei rebuilt distributor, hooker ceramic headers, everything new. i broke engine in at 2000 rpm for 30 minutes
vacumn advance does advance when plugging in vacumn to distributor. set timing at 10 degrees BTC. Originally stated with accelerator squiters not squirting, so I took apart and got working then had to move rod to closer hole for mor fuel deklivery which solved a major bog and backfire problem when stsbbing throttle. but now I have this bog or backfire at mid to heavy throttle during acceleration. Egine idles pretty smooth and quick throttles seem very responsive. I richened up main jets 1.5 stages but barely any difference. Iput timing light on each spark plug wire looking for response and seems to fire on all cylinders. I rechecked several times the firing order to make sure it is right. Engine also idles with approx. 45 psi. has a fairly mild cam with hydraulic lifter and factory rocker arms set for 0 lash. Nothing knocks or pings but backfires and stumbles on acceleration over about 30 mph and has no power. Hooked to a untouched turbo 350 that worked before. Engine hhas good vacumn and and brakes and transmission seem okay. Any ideas out there. Fuel or ignition? Would to tight a valve setting cause this but still idle fine? Also has a hard time starting after it is warmed up for 5 to 110 minutes. need to let it cool down and starts fine, I attributed this to factory starter with headers and no heat shield on starter. Any help appreciated.
vacumn advance does advance when plugging in vacumn to distributor. set timing at 10 degrees BTC. Originally stated with accelerator squiters not squirting, so I took apart and got working then had to move rod to closer hole for mor fuel deklivery which solved a major bog and backfire problem when stsbbing throttle. but now I have this bog or backfire at mid to heavy throttle during acceleration. Egine idles pretty smooth and quick throttles seem very responsive. I richened up main jets 1.5 stages but barely any difference. Iput timing light on each spark plug wire looking for response and seems to fire on all cylinders. I rechecked several times the firing order to make sure it is right. Engine also idles with approx. 45 psi. has a fairly mild cam with hydraulic lifter and factory rocker arms set for 0 lash. Nothing knocks or pings but backfires and stumbles on acceleration over about 30 mph and has no power. Hooked to a untouched turbo 350 that worked before. Engine hhas good vacumn and and brakes and transmission seem okay. Any ideas out there. Fuel or ignition? Would to tight a valve setting cause this but still idle fine? Also has a hard time starting after it is warmed up for 5 to 110 minutes. need to let it cool down and starts fine, I attributed this to factory starter with headers and no heat shield on starter. Any help appreciated.