what octane do you use?

[m3f_sameguy]

I've only ever run 93 in my M3, but my last car (95 mitsu GSX) got an accidental tank of 87 (thanks to my wife (honey I filled up your tank and it only cost $11)) It felt like I lost 20-30% across the rev band. I assume the knock sensor was retarding the timing. Granted the GSX was running a big turbo, and 15lbs of boost, so it's sort of talking apples and oranges here. If you feel lower octain reduces your performance and you don't mind, well, run with it. Personally I want as much as my ride offers, so it's 93 for me.

[m3f_MattRS2k]

In the UK I run on BP Ultimate or Shell Optimax, both 98 octane. There was a stick on my car by the fuel guage saying the M3 should only be run on 98 octane fuel. Is this beacuse mine a Euro M3 Evo (321bhp)?

[m3f_Sirius_880bd69485]

In the UK I run on BP Ultimate or Shell Optimax, both 98 octane. There was a stick on my car by the fuel guage saying the M3 should only be run on 98 octane fuel. Is this beacuse mine a Euro M3 Evo (321bhp)?



Yeah prob. The euro motor has a higher compression then its US counterpart.

[m3f_Max M3]

In the UK I run on BP Ultimate or Shell Optimax, both 98 octane. There was a stick on my car by the fuel guage saying the M3 should only be run on 98 octane fuel. Is this beacuse mine a Euro M3 Evo (321bhp)?



Not really... it's because the European Octane ratings are scored differently than in the US. 98 octane in EU is about the same as 93 octane in the US.

[m3f_Angella_c036ec6b5f]

I run 93, and find my car is a little happier... I've actually started using gas from the kroger across the street from work...



I talk to the guy who runs the fuel in for them... they buy only shell and mobile... I can stand behind both of them, and I get 7 cents off per gallon with my Kroger Plus card : )



I've used the cleaners, but only if the car is really asking for it... when my sister was using my old sunfire, she was putting cheap gas in it - I ran a bottle through, it was happy again... so I only use it if it needs it, not just for the heck of it. I'm also not convinced that the $7 fuel cleaner is better than the 99 cent stuff from odd lots... so when I use it, I use the cheap stuff. : ) Hopefully you won't ever have to use it - if you think you need it, try a tank of the really good gas first : )



I do not run BP unless someone is holding a gun to my head : )