Running a high compression engine on pump gas

[Lynn]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: VintageMusclecar</div><div class="ubbcode-body">The 496 in my Chevelle has 11.2-1 compression with square port closed chamber heads, and runs perfectly on 92 octane. The key(s) to making it work are 1) cam timing (needs to bleed off some cylinder pressure @ lower rpm), keeping the engine coolant temps ~160°-170°, and a nice, conservative timing curve--in this instance, 14° initial and 36° total, but it doesn't come in fully until ~4000 rpm. (no vacuum advance either)

FWIW, YMMV. </div></div>

I agree with all of the above, but would add one thing. Tight quench. I have it down close to .030 (don't think you want it that close on big block) on my turbo motor, and it never pings even with 15 psi boost.

Of course, this doesn't help you if the engine is already together. If you are still in the building stage, you can choose your headgasket accordingly.

I rarely see this discussed as a weapon with which to combat detonation, but believe it is a vital piece of the puzzle.