The MSD coil that Kayo and others have talked about is a direct swap for the original Bosch unit, It bolts right in and puts out more voltage. Accel also makes a high performance unit just the same as the MSD unit, only at about half the cost. Try an Accel # 8140, about $27. I've been running this unit ever since we did the "Dyno Days" testing last fall and it has fixed the ignition problems we found on the cars on the top end. I just think the original Bosch units are getting weak after 18 years. Marty