Earlier this year the 351w in my 87 got to where it wouldnt crank right away like it used to. You could drive to the gas station, grocery store or whereever and when you leave, it would act like it was choked out or wasnt getting a spark but if you let it sit for a few hours it would crank just fine. I know the iginition is ok because the plugs, wires, cap, ect... aren't even a year old yet so the next thing I checked was the ignition module and it tested fine. So what else could it be? Could the carb be messed up or could the engine be ready for a rebuild? Its only got 234,000 miles on it which isnt exactly low miles but its been well taken care of.