im not running timing control but I did change to a hall effect chip in my hei dizzy.. I have the car running pretty good.. I changed the radio and solved the cutting in and out issue... it was the radio.. all the wiring is exactly the same.. it was getting interference from the efi install... the retro sound had leads for the aux im thinking was acting like an antenna.. I don't think I solved the cold start issue either.. its just gotten warmer and the car is starting better.... still not what I was expecting... I was expecting it to start like a new car... If im being honest, atleast at this point im sorry I spent the money.. doesn't really start better or easier than a good tuned q jet