Hello all, I will start by thanking you far taking time to read and reply to this. I have a 1968 Mustang with a 302 and a Demon 625cfm Road demon jr. and a relatively mild comp cams cam (I think it's specs are something like 168 degrees and .460 inches of lift) Right now it is set at about 16 degrees advance (the cam manufacture reccomends 14-20) and I have tried all the way from 10 degrees retarded to 30 degrees advance. It has a c-4 transmission that was JUST re-built, and I dont know how the engine ran before the rebuild because they were rebuilt at the same time. Now, the problem is that the engine runs GREAT in park or neutral, but as soon as the transmission is shifted into gear, the rpms drop (as the should, I think) and the engine soon dies if it's not given gas. The engine doesnt pull under acceleration, either. The car has power breaks, which are somewhat "soft"....which leads me to believe that there is a vaccum leak, yet the engine will pull 10-15 inches if the timing is set right. The vaccum needle usually jumps around +/- 1 inch too. I'm not sure if that amount is typical for the cam described above. Is there a vaccum leak? Would a leak cause the problem described? What else could it be? Does anyone have good methods for finding vaccum elaks? I really have no idea how to search for them. Thanks for all your help!! If you need more info, ask, I'll check this post regularly.
-Dan