Still having issues with my 383. Stock HP block, forged crank, diamond pistons on factory rods, comp cam hydraulic roller, ported 906 heads, cast intake, on my 3rd carb. Couldn't get the last dual feed double pumper from pro-systems to run right, so went to a QFT SS-680 dual feed, electric choke. Now running digital point conversion. Running 20 degrees initial timing, and at all in 3,000 RPM at 34 degrees. Running 93 octane fuel.
Trouble shooting so far:
Battery had some bleed down issues as it would never hold past 12.4 volts overnight, however after hooking up the gauge to it and driving it gave a 14.5 v reading the entire time.
Fixed the distributor which seemed to have a little bit too much play as the rotor was making contact with the contacts in the cap.
Dialed in the AFR almost perfect on idle and in the primary circuit.
Had an issue with dropping push rods 2-3 times and put a new set of comp hydraulic lifters in. Re-sealed the intake again.
Heres the issues:
Around town the motor idles and runs the primary circuit beautifully. Put my foot into the gas for a quick launch and no power and pops through the exhaust OR the carb depends on the day. On the highway, again the primary circuit runs great and I can make decent pulls to maintain highway speed. The SECOND I bury my foot into the gas I lose power and pop through the carb and/or exhaust.
So thinking it may have been electrical we seemed to have debunked that, now thinking it could either be a valve sticking or intake leak?? Compression test with cold engine and WOT showed 180 PSI in all banks. Compression seems high which may explain a dieseling problem I have off and on.
Pulling the plugs showed 3&4 were good, the rest are soot covered. The plugs in the back are worse than the ones in the front. Have had the intake off about twice and was careful to reseal the thing up nice. Could I be looking at an intake seal problem? Wondering if it was an intake seal/valve sticking would I have problems just on the secondaries??
Trouble shooting so far:
Battery had some bleed down issues as it would never hold past 12.4 volts overnight, however after hooking up the gauge to it and driving it gave a 14.5 v reading the entire time.
Fixed the distributor which seemed to have a little bit too much play as the rotor was making contact with the contacts in the cap.
Dialed in the AFR almost perfect on idle and in the primary circuit.
Had an issue with dropping push rods 2-3 times and put a new set of comp hydraulic lifters in. Re-sealed the intake again.
Heres the issues:
Around town the motor idles and runs the primary circuit beautifully. Put my foot into the gas for a quick launch and no power and pops through the exhaust OR the carb depends on the day. On the highway, again the primary circuit runs great and I can make decent pulls to maintain highway speed. The SECOND I bury my foot into the gas I lose power and pop through the carb and/or exhaust.
So thinking it may have been electrical we seemed to have debunked that, now thinking it could either be a valve sticking or intake leak?? Compression test with cold engine and WOT showed 180 PSI in all banks. Compression seems high which may explain a dieseling problem I have off and on.
Pulling the plugs showed 3&4 were good, the rest are soot covered. The plugs in the back are worse than the ones in the front. Have had the intake off about twice and was careful to reseal the thing up nice. Could I be looking at an intake seal problem? Wondering if it was an intake seal/valve sticking would I have problems just on the secondaries??