Unless you are out on the big roads flogging that thing like a state police car. I have an M103, I run it all the time on 89 octane and never so much as a hint of a ping and I can and once in while do overload it, by not shifting quickly enough. Now I don't do that often, but just once in a while I forget that it won't shift by itself, as it is a five speed. My M103 likes the revs and I drive it hard, not to abuse it, but I don't think it will carbon up the way I drive it either. Mine gets about 60 miles a day on local metro roads, but no high speed interstate driving. And I think that sustained high speed interstate type driving is where I would be using the high octane gasoline.

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Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!