After following Chris' problem with the seals in his 427w, I was relieved to see I wasn't having the same problem. However, I seem to have perhaps a different problem.
My set up is a Ford Racing cate 427w, performer rpm airgap manifold, and a 750 DP (4150 HP street) carb. When I first started it, it seemed to be running very rich and blowing some light black smoke. The fuel pressure is correct at 5.5 psi and the floats are set properly. It definitely seemed to be a fuel problem and after troubleshooting the carb and noticing fuel stains on the carb base gasket and fuel in the intake manifold, I replaced the 750 with a new 650 DP that I know works as it was on my 66 Mustang. I also changed the
oil as it smelled like fuel and replaced the plugs. Today I finally got back to it and I'm able to get about 15" of vacuum at idle (bounces between 13 and 15) with all four idle mixture screws out 1/2 turn, but it still seems to be missing, blowing some smoke, and falls over when I give it gas under load. If I rev it in neutral I can feel and hear it missing. I haven't hooked up the wideband, yet, and I guess it is possible the MSD distributor is causing the miss, but I welcome any other suggestions.