Rich rich rich just to idle in gear

[69sport]

You should be able to see the slots when butterflies are closed. Also you mentioned secondaries being open. What’s with that?

I would have my curb idle screw in really far before opening the secondaries so I opened them up to turn the idle down without stalling the car, that’s what made me think it just needed more o2 so I drilled 1/8 holes in the throttle plates but that didn’t necessarily help at all, so now I’m thinking fueling issues?

 

[69sport]

What is your fuel pressure? Do you have a regulator? Have you ever measured it? Sounds like it might be too high to me. I had an electric fuel pump way back when on my old 383 Challenger. I did, however use a pressure gauge and a regulator. It was noisy and the car never ran reliably with it. I went back to a factory mechanical pump & it was much better! I assume that your exhaust pipes are black or very dark inside which indicates a rich mixture. Good luck!

I have no idea what the fuel pressure is, I can tell you the pump was installed in the 80s so it’s probably time for a new one anyway. I wanna stay electric if I can, do you have any recommendations and what psi should I be running?

 

[4vnut]

I think you need to try a different carb due to: Never been able to lean it out, drilled holes in throttle plates which is acceptable with bumpier bump sticks but how big did you drill them? Shouldn't be over .125 in imo. Secondary plates are open (again acceptable) I assume for more air to lean it some so it probably isn't running rich. The driver's side air mixture screw is funky? And you have had backfire's thru this carb. It probably has other issues we can't diagnose adding to itself.
I would try another known good carb. After you get the timing sorted out.

 

[Houle #382]

Hey all,

I got a 318 with 340 heads, a Holley 1850 600cfm and hemi street performance cam and I’ve never been able to lean it out. The car runs super rich with the idle mixture screws out a turn and a half. The driver side screw is a bit wobbly and doesn’t respond like the passenger side screw which is suspicious. I drilled 1/8 holes in the throttle plates thinking that would help but I think it made it worse, it’s like it’s not getting enough fuel without the idle mixture screws turn out so far otherwise my vacuum drops from 15 to 5 going into gear and i stall. I got the secondaries open up about two turns, I can’t get it to idle without them open so far.

Is this a sign of a bad electric fuel pump or just poorly tuned carb/wrong carb for the car

 

[Houle #382]

Hey all,

I got a 318 with 340 heads, a Holley 1850 600cfm and hemi street performance cam and I’ve never been able to lean it out. The car runs super rich with the idle mixture screws out a turn and a half. The driver side screw is a bit wobbly and doesn’t respond like the passenger side screw which is suspicious. I drilled 1/8 holes in the throttle plates thinking that would help but I think it made it worse, it’s like it’s not getting enough fuel without the idle mixture screws turn out so far otherwise my vacuum drops from 15 to 5 going into gear and i stall. I got the secondaries open up about two turns, I can’t get it to idle without them open so far.

Is this a sign of a bad electric fuel pump or just poorly tuned carb/wrong carb for the car???

Buy yourself the Edelbrock 650 AVS2 and hook your vacuum line up to the manifold side of the carb.