Mopar Fueling Problem

I am having troubles with my engine. I believe that it is a fueling issue but not competly convinced. I have a 1969 Barracuda with a built up 318. I am running a hot solid lift cam, worked 360 heads with proper springs for the cam, full length headers, MSD 6 HVC-L ignition system, Mallory Unilite, Accell 8mm wires, Holley 750 with vac secondarys etc etc. Here is the problem....I was running a Dual Plane LD4B intake on it and wanted to go to a single plane. I purchase an M1 and switched over. The engine was running well prior however I could feel the intakes limits after about 5 grand.

I switched the intake, plugs and wires only! I am still running the same carb, and everything else. The problem is that at about 3500 RPM my engine starts to stumbe and act life its starving for fuel. I thought that maybe my lod pump was not performing at its best so on went a 150lph electric and regulator. I have more than enough fuel to feed it now and it is still doing it.

I switched to a 600 Edelbrock that I used to run on the car and it still does it with the smaller carb at the same RPM.

I can't seem to find any vacum leaks or any other mechanical issues. Timing is good also.

Does anyone have any ideas or have they ran in to this before?

Author: admin