What difference if any does gapping a plug from lets say .045 to .040 or from .045 to .050 How does it effect the plug for burnng off the fuel?
Thanx

My understanding:

The bigger the gap, the more efficient/complete the combustion.

The bigger the gap, the more energy it takes to jump the gap.

The bigger the gap, more the more likely the plug won't fire under heavy throttle / high cylinder pressure (because of not enough energy to jump the gap).

-Bob Cunningham

Thanx for the reply Bob.So would you say that closing the gap alittle on a plug would take care of some detonation problems at higher RPM's?Like say sifting @6000? Thanx again

Detonation? Probably not. You might try a colder plug if you are having detonation, or backing off the timing.

As you can imagine, if the ignition system (coil) can't generate enough energy for the spark plug to fire, you'll get more of a rough-running engine, or a miss.

On the other hand if your spark plug is getting too hot (because the heat range is too high), the spark plug will ignite the mixture prematurely because of the heat- in this case a colder plug will help. (A colder plug has the electrode less exposed in the chamber, which prevents it from heating up so much)

-Bob Cunningham

Thanx Again Bob.Think I'm going to go with a colder plug.See what that does.Also ,Igot my engine temp down from 200 to 180,and that seemed to help with the pingig as well.

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