If my manual says use octane 91 (back in 1976)...is that the same rating used today? I've heard differently, and that I should be using the 89 (mid grade) octane instead.

i use 89 becouse i dont think they had 91 20 years ago, you can realy feal the diffrence in perfomance with diffrent gas, i do think 91 might not be to good, it ripps the car, and makes it fly realy quik, burns not so slow either.

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I can do 111mph with no gas, no oil, and no power staring, threw traffic. Can anyone else do this one a 20 year old car? I think not.

I used to have a g35, now I took this Benz and made it quicker, more agile, and much roomier then the g, **** Japan rock the German engineering.