Lean pop off idle?
Hey guys, I’ve been trying to get my fresh built 440 RamCharger running right, and haven’t had much luck. I haven’t been able to spend much time with it lately, so I’m hoping someone here can point me in the right direction. I set the base timing at 16btdc, (haven’t checked total timing yet. I know I should). At first I bolted the carb on, and was able to break-in the engine. Whenever I try to accelerate at all, it falls on its face and pops out of the carb, sometimes stalling the engine.
Here’s some details.
440 big block/manual transmission
Holley 770 street avenger (single pumper)
Aluminum dual plane intake
452 iron heads
Forged aluminum pistons (9:1 compression)
RV cam (see pic for specs)
Mopar electronic vacuum advance distributor
Mopar blue ignition box
440 source 10mm plug wires
MSD Blaster coil
Autolite #85 plugs
Full length headers with 1 3/4 primaries
Edelbrock mechanical fuel pump
New 3/8 fuel line/filter all the way to the clean tank
87 octane fuel.
I followed Holley’s instructions on setting the accelerator pump, so it starts pumping fuel as soon as the throttle is touched. I’m confused on the curb idle screw, because some say adjust it until you can barely see the transfer slots, and some say you shouldn’t be able to see them at all. I’m also confused on the sizing of the accelerator pump nozzle and diagram sizing, as some say for heavier vehicles, you need a larger one, and then some say a smaller one.
I can see fuel through the little sight glass on the sides of the bowls, it’s towards the bottom of the window.
I’ve tried tuning the idle air screws with a vacuum gauge, but that didn’t seem to help, I was able to get about 16Hg at idle. I’ve checked for vacuum leaks and don’t believe I have any.
Any input is appreciated.
Thanks, Craig.
Hey guys, I’ve been trying to get my fresh built 440 RamCharger running right, and haven’t had much luck. I haven’t been able to spend much time with it lately, so I’m hoping someone here can point me in the right direction. I set the base timing at 16btdc, (haven’t checked total timing yet. I know I should). At first I bolted the carb on, and was able to break-in the engine. Whenever I try to accelerate at all, it falls on its face and pops out of the carb, sometimes stalling the engine.
Here’s some details.
440 big block/manual transmission
Holley 770 street avenger (single pumper)
Aluminum dual plane intake
452 iron heads
Forged aluminum pistons (9:1 compression)
RV cam (see pic for specs)
Mopar electronic vacuum advance distributor
Mopar blue ignition box
440 source 10mm plug wires
MSD Blaster coil
Autolite #85 plugs
Full length headers with 1 3/4 primaries
Edelbrock mechanical fuel pump
New 3/8 fuel line/filter all the way to the clean tank
87 octane fuel.
I followed Holley’s instructions on setting the accelerator pump, so it starts pumping fuel as soon as the throttle is touched. I’m confused on the curb idle screw, because some say adjust it until you can barely see the transfer slots, and some say you shouldn’t be able to see them at all. I’m also confused on the sizing of the accelerator pump nozzle and diagram sizing, as some say for heavier vehicles, you need a larger one, and then some say a smaller one.
I can see fuel through the little sight glass on the sides of the bowls, it’s towards the bottom of the window.
I’ve tried tuning the idle air screws with a vacuum gauge, but that didn’t seem to help, I was able to get about 16Hg at idle. I’ve checked for vacuum leaks and don’t believe I have any.
Any input is appreciated.
Thanks, Craig.
