I have the MSD DIS-4 with Taylor pro wires and stock coil packs. After I put all that together I have had a misfire ever since. The wiring is correct, I think the stock coil packs were the problem. It would missfire in the powerband no matter where the throttle was around 2200-2400 & 3200-3400. I say I think it was the coil packs because I'd put the MSD bypass harness clip in and return it to factory ignition and it would still misfire. Others told me it was the cold air intake with 87 mm Pro - M, but I had a C&L with K&N and it did the same thing.