I have the exact same problem. I am using two internal VB921 transistors to drive the stock coil (I think you are too). No matter what I do, I can not get the car to run right with any spark table. It will idle smoothly and I can get up to about 2500 RPM. After that, it just breaks apart. I have a connector that allows me to switch in between MS spark and stock ECU spark. I switch back to stock and the car runs perfectly. Today, I am going to get one of those 4G63 power transistors and see if that works. I'll post if I get it figured out.

Corbin

'95 ESI-T
Now with more power and fewer leaks



Gimme fuel...Gimme fire...Gimme that which I desire