iridium18

Am interested in any technical / testing data that may be out there. The GLS450 states 91 octane must be used. My favorite and convenient station carries 87 / 89 / 93. So, without having to "blend" every other fill-up, I am wondering if 89 is really detrimental, or is it simply marginally impactful on power and fuel mileage. Thanks,

Plutoe

If you want something other that HS----go to the American Petroleum Inst site. There you can spend your time reading and answering your very technical question.