High Octane Fuel

[bimmers4life]

Got a question, will high octane 93+ or even as high as 105 make any performance gain on a 99 M3 with naturally aspirated engine and non chipped ECU?

[Lord Vader]

Long story short, no. If it was Forced Induction maybe, due to higher compression ratios it would help reduce detonation. On a stock NA car it will do nothing but waste your money.

Go to Top Tier Gasoline. using a Top Tier brand of gas would be better for your car.

[bimmers4life]

Nice, thanks for the info. So if i supercharged the car down the line I would feel gains from a higher octane? Or if I were to just buy a 135 with the turbo'd six?

[Lord Vader]

If you were to Turbo it, then possibly. Depends on a lot of factors, including compression ratio. Supercharging usually keeps the same compression ratio IIRC. I was looking into getting the Active Autowerks supercharger kit for my car and with the software they use, they tell you to use at minumum 91 Octane. I have 94 octane available at several gas stations and i really dont think the cost is worth it. Even with the 135, I dont see the cost worth it. Run 91 octane and you will be fine.

[rivroshaun951]

Just in case one opinion isn't enough. No it will not.

[RoadsterMadness]

Indeed - if your car is TUNED for it - sure there is a big difference. DINAN tuned my stage 4 race kit S3-R ///M3 for 100 octane or greater and it performs way better. On an NA car - save your $$$ - although I'd still do 93 not 91.

[bimmers4life]

Would there be gains on a 93 from a 91?

[RoadsterMadness]

I think so and feel it in my pants