I have been hearing about this misfire issue with cars running the fast system & msd dis box together.Was on the dyno today with a turbobuick.It had a misfire that would start anywhere from 5700 to 6250 on up.Sent the fast box back to fast and they made a change to it same problem.Took the msd out of the system problem went away.So on the last pull decied to plug it back in.The car went back to missing at 6250.Now we dont no what to do.So decied to check the switches on the msd box again,all looked fine until we got to the max rpm rev limit.They were all off thinking if there off the rev limiter is off not the case.With them all off its set at 6250.Turned them all on now its set at 10,000 made a pull on the dyno pulled clean all the way to 7300. Then we met our goal 856 rwhp.Made some calls to all the people i know with the problem checked there rev limit switches they were all set at 6250 with the switches off.So i think we solved all the misfire problems we were having here.If anything changes i will let you know.I hope this helps.
Pete Barton
Pete Barton