100 octane fuel

[GS455]

Has anyone tried mixing fuel in their MS3? Here in Las Vegas we have 91 octane premium and 100 octane racing fuel.

 

[SwampAss]

I'd wager no added benefit with 100 octane unless the car is specifically mapped with a 100 octane program.

 

[KYMP5]

yea, wouldnt do you a whole lot of good without tuning for it, and by tuning for it i mean crazy ass build and engine management. We've dynoed several vehicles (cars and bikes) in the past running it on mild turbo setups with basic fuel management, and its just not really worth it IMO. Now on some of the nastier setups we've tested, we've seen 50 horse to the wheels, but those cars are built for it and just detuned for pump gas.

 

[Speedy3]

I haven't tried custom mixing like with toulene, but I have used "104 Maximum Octane Boost" over the counter. I have a thread ("Mazdaspeed 3 Stutter") talking about a stutter problem that I think is associate with the octane booster.

 

[quiet desperado]

yea, wouldnt do you a whole lot of good without tuning for it, and by tuning for it i mean crazy ass build and engine management. We've dynoed several vehicles (cars and bikes) in the past running it on mild turbo setups with basic fuel management, and its just not really worth it IMO. Now on some of the nastier setups we've tested, we've seen 50 horse to the wheels, but those cars are built for it and just detuned for pump gas.

The DISI ECU seems to be able to adapt it's tune to higher octane fuel by advancing timing to the point where it starts to detect pre-detonation. MS6 owners running racing fuel say the engine runs substantially stronger and smoother. Probably not 50 horses worth, though. Apparently you need the Vishnu-tuned Xede piggyback from Bell Engineering wired in to allow that much timing advance. Oh, yeah, and to lean out the A/F ratio and do other things as well.