Originally Posted by chevyrestore
Hey guys. Ive got a 1980 454 motor in a 59 chevy truck.
My problem is ive got an aftermarket HEI setup (procomp distributor with MSD blaster coil) (the square coil not the cylinder). When the motor gets hot and its hot outside the truck starts to misfire, then when its cool out it works fine. I replaced the coil once and that fixed it but now that its hot outside again its happening again.
Could this be a wiring concern or a physical outside air temperature too close to the coil causing the problem? I have a EZ wiring harness installed in the truck and no ballast resistor on the setup.
Not sure if I need to go one step farther and drill the firewall and mount the coin in the cab or if I need to be fixing wiring.
Any help is appreciated, thanks everyone
Given that ProCom sells about a half dozen different models of this thing, the question has to arise as to what is the part number?
ProComp in the past has had a lot of problems with the electronics and electrical parts. I don't use the stuff but know several people that do. I'd go back over the instructions to discover what the connection voltages should be then check them out. If the coil or the electronics are under volt and in the case of the coil overvolt they/it will run hot.