LT1 &4 are "OPTI-SPARKS"
If i remember correctly,with the EST by-pass wire disconnected,the timing is set at -6.It's been many years since i had a distibutor vette,91 was the last year.
If i remember correctly,with the EST by-pass wire disconnected,the timing is set at -6.It's been many years since i had a distibutor vette,91 was the last year.