Can the gap on Rapidfire plugs be opened beyond the factory setting of .035 despite AC specifically stating that this setting remain unchanged? I'm asking because I just installed an MSD ignition and coil and the instructions recommend a plug gap of .050. My engine (255hp 350) runs great with the Rapidfire/MSD combination, but I'd like to take advantage of what a wider plug gap can offer.

Thanks,

Brian R

Brian,
What Rapidfire plug are you using? Are you running a set of older heads? The Rapidfire #1 plug fit Chevy heads that use the 5/8" plugs, and are gapped at .045.

You can adjust the plug gap to your own spec, but try to keep the ground electrode parallel. If it is angled it will shorten plug life.

Skip,

I'm using the #7 Rapidfires as prescribed for my '69 Malibu. As for the heads, they are original to the car as is the rest of the motor.

Thanks for responding, you too Tony

Brian R