So i have installed a Blueprint Engine with 9:1 compression that dyno'ed 308 hp / 344 ft lbs torque. I installed a dual plane aluminum intake, a 1/2 phenolic spacer, a new Holley 4160 with vacuum secondary's, and an HEI distributor. For the drive line i have an AOD with 2400 stall torque converter and 3:73 gears.
I have a hesitation when i hit the throttle.
Would the mechanical fuel pump cause possible issues? I noticed when i changed the carb that the fuel had run back down the line and needed to pump fuel back up the line to fill the carb's bowl. If the internal check valve is bad could the pressure be low and that cause a hesitation? At and idle it appears to keep the bowl full. After the take off it seems to run fine.
For timing the HEI distributor will show my timing curve 14 degrees at idle and 32 at 3500 rpm. I had a local shop check it and he said with his timing light he was getting 16 degrees at an idle and 36 at 3500 rpm. But here's where i'm confused... I DON"T have the vacuum advance attached because of that curve (the mechanical innards are advancing it) . If i set the base idle at 14 degrees WITHOUT the advance hooked up (and yes, i sealed all vacuum ports etc). Could that be causing problems? Does having the vacuum advance connected affect initial timing on take off? Should i retard the timing further then hook up the vacuum advance?
Any thoughts or ideas would be greatly appreciated.
I have a hesitation when i hit the throttle.
Would the mechanical fuel pump cause possible issues? I noticed when i changed the carb that the fuel had run back down the line and needed to pump fuel back up the line to fill the carb's bowl. If the internal check valve is bad could the pressure be low and that cause a hesitation? At and idle it appears to keep the bowl full. After the take off it seems to run fine.
For timing the HEI distributor will show my timing curve 14 degrees at idle and 32 at 3500 rpm. I had a local shop check it and he said with his timing light he was getting 16 degrees at an idle and 36 at 3500 rpm. But here's where i'm confused... I DON"T have the vacuum advance attached because of that curve (the mechanical innards are advancing it) . If i set the base idle at 14 degrees WITHOUT the advance hooked up (and yes, i sealed all vacuum ports etc). Could that be causing problems? Does having the vacuum advance connected affect initial timing on take off? Should i retard the timing further then hook up the vacuum advance?
Any thoughts or ideas would be greatly appreciated.
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