There might be a slight increase in exhaust manifold temperature, as premium gas burns slower than regular and some of it might still be burning as it leaves the cylinder. You can advance the timing a few degrees if you run premium all the time and get the burning process started a little sooner. Just be careful not to advance it so far that the engine pings when running regular gas.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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