[Wayne 962]

Someone recently asked me this question:

To: pelicanparts@csi.com
Subject: Octane Q & As


Great Web Site! Getting better all the time. My Question is: I can get 100
octane fuel at my 76 station. I have been mixing it with 92 octane in a stock
car I run. ( 1981 Monte Carlo, 305 ci.). No problems and higher RPM ability.
Can I run pure 100 Octane in my stock 1972 1.7 914 w/FI ? Can I run pure 100
octane in my 1975 3.0 911 (FI) ? Can I cause damage by using this fuel? By
the way, this fuel cost $ 4.00 per gallon. No Problem ! Thanks,
Gizmonaz@aol.com

Hi there. There is a FAQ about gasoline on the site; you can find it by doing a search for it, or it's in the tech articles section of both the 914 and 911. The FAQ has much more info that I could ever know.

As far as I do know, running the 100 octane fuel in your car will not hurt it at all, but even more important, you won't see any performance increase. The reason why the racers run the high octane fuel is because they have high compression engines. The high octane fuel reduces knocking, which increases as the compression increases. So using the fuel with your street cars would be a bit wasteful.

On the other hand, running low-octane fuel tends to make the fuel burn quicker, and thus hotter. Running about 93 in the older cars is what our race machine shop recommends, primarily to keep the heads (especially important on the air cooled cars) cooler

Thanks,

Wayne