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Afternoon Board-

Living here in the land of the free (no left coast) 101 octane is readily available, albeit a little expensive relative to 93. Anyway, gassed ole Red up with 101 yesterday and I SWEAR there is an appreciable difference in smoothness and acceleration. Is this is my head or will an Octane this high allow the computer to advance the timing enough to make a difference? The fellow at the gas store couldn't believe ole Red had 11-1 CR until I showed him the owners manual. Thanks for input!

KCD
cherrsagai
 

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KCD:

More octane slows the detonation rate of the air fuel mixture. The higher octane works up to a point. Higher octane is better at lower RPM's where pinging is likely to occur when the engine is being dogged.

You probably are seeing some ignition timing advance as a result of the 101 compared to what you were running. But there is a maximum limit to the timing advance; the ignition timing computer does have a maximum advance.

Does that occur at 93 or 94 or 95 octane or 101? Don't know. :3:
 
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