i have a b17 with ctr pistons a .054 head gasket to lower the comp with simple bolt ons it has a blaster coil msd plug wires and cap it runs great for a couple weeks then starts hesitating at high rpms put a new coil it runs great I went stock it lasted 4-5 days at the most

 

it sounds like u have something wired up wrong, possibly defective plug wires. You do have a msd box ? right

 

We had a car that would destroy a coil or ignitor in 3 days. We put a new coil and ignitor in together and it never had a problem again. Just a suggestion.