Thank you Clauser1, I may try running the 92.5 with ethanol for a tank or two.

One more question, you know of any good MB tuners in the Chicago area? Someone with turbo or supercharger experience? I ran across one webpage, but damned if I can find it now!

Thank you!

__________________
Brian W.

01 S55 AMG Silver
01 CLK55 AMG Silver