Hey,I gap my plugs @ .060 w/ my HEI in my 70 big block
I tested my Nova drag car once to see if increasing the plug gap really added more HP. The car had a MSD 7 ignition system. I gapped the plugs at .035, .045,.060, and .075. I didn't see a difference in the ETs, so I don't think it helps. What large gaps can do is to create a miss when the ignition system is over taxed and can't fire the big gap. I see no reason to go over .045" . Just my $.02
BL
