<VV> 100 Octane Fuel

[Dave Thompson]

I just found a gas station in Ontario, California that has a separate gas
pump that dispenses 100 octane fuel for about 20 cents more than their 91
octane premium. It is about 40 miles from my home. That got me thinking.

 

I have the timing retarded on my 63 spyder to stop it from pinging on 91
octane. I'm guessing that if I run the 100 octane I could advance it a
little. If I ran 100 octane without changing the advance would I see 20
cents a gallon's worth of extra performance or would I have to change the
timing? To be honest, if there is really no advantage without changing the
timing, to me, it's not worth changing it. Would there be any advantage or
disadvantage to running a tank of 100 octane now and then? Would there be
any problem mixing a partial tank of 91 with 100 octane? I bet not, just
less than 100 octane performance.

 

A buddy of mine usually uses 85 octane in his Piper Cub airplane. However,
now and then he can't get it at an airport he is visiting. When he uses 110
low led avgas he says that he sees a noticeable difference in engine
performance without making any engine adjustments. Is mixture control
considered an adjustment? By the way, he does have an STC for auto fuel use.


 

 If it will give me a little boost in performance, I'd like to "give the dog
a cookie" every once in a while.

 

Is there a website that lists gas stations that carry 100 octane?

 

 

What do you guys think?

 

Dave Thompson

63 Spyder Vert

Westminster, CA