I think for the most part all a wider gap does on a NA engine is work the ignition system and wires harder.

I seen a car a few years back that wouldn't run with a .040 gap and was fine at .035..

I run mine at .035 on gas and tightened it up to .030 when I put alky on it.

Blower, turbos and NOS are a different story.


67 Barracuda street/bracket car 11.27-119
68 Dart 502 BB 8.70s-152
414 cid SB Dragster 7.65-174