Need some advice. My 351 Windsor just will not run smooth or drive smooth. It has a Gearstar AOD which won't shift out of 4th gear until almost stopped causing severe bucking and it shifts too soon (needs more pressure I think). The real problem is the FAST EFI on the Edelbrock Performer RPM air gap manifold. It just won't run smooth and stumbles just like a carb would. It runs rich no matter what I do. FAST says the O2 sensor is too close to the 4 pipes as the come into the collector (I'm about 1 1/2 inches away just like many other headers I've seen with O2 bungs). My muffler and extension hook on about 3 inches from the O2 sensor and I've done everything I can to stop the leaking at the slip joint. If I can keep the engine above 2000rpm the car runs decently. Opinions? Too much manifold for the application? The car is a cruiser. The engine only made about 365hp on the dyno with a 650 carb. The dyno shop couldn't hook up the efi for tuning purposes.