101 octane or more gas

[Woody_393]

I'm not sure it matters. The distillation curve is more important then the octane (unless of course you have knock) rating anyway.

If you don't burn all the fuel, you're just losing power regardless of the octane.

[FFRacing11x]

Hmmm, ya think the 87 octane NUTEC I run in my 13.8(calculated) YZF is too low? Is 13.8 actually 13.8 when you calculate cam overlap? Is $20/gal too expensive? Is the theory of running as low an octane as your motor can survive on will make the most HP wrong? Is too rich REALLY better than lean? When is lunch? Tdub

[Woody_393]

LMAO... yeah, when is Lunch anyway?

In Tdub's humor, he does have a very valid point. You will get more power with good fuel (be it race fuel or whatever, as long as all other things are good, e.g., distillation curve etc) with an octane rating that is just above where it will Knock.

[ossagp]

Just the kind of thing I like to read. We are all "knowledge products" of those we consider authorities. One of the things that I have always maintained got a little help here: Tryce runs an 87 mon fuel in an engine with nearly 14-1 compression. It obviously has the ability to resist preignition that is necessary. Obviously of a very consistent quality. I have always said that with consistent quality I can jet for just about any any octane rating. From gas to alcohol.

Someone mentioned that gasoline does not vaporize as it travels to or into the cumbustion chamber. He even name drops (but not in a bad way) something about grad school. He is correct in that all of it can't possibly evaporate. What most have come to call atomization does indeed seem to bear out a percentage of the fuel evaporating. (A significant part of the cooling effect comes from that evaporation.) That lack of evaporation has made direct injection of two strokes particularly tricky, thus making them harder to "cleanup" in some of their more traditional applications such as outboards. I am sure most of you are aware of some of the advancements in production two strokes that my be widely termed "indirect injection", as well as designs similar to Honda's Exup two stroke from years back. (that engine was combustion ignited after it reached a certain rpm). Who knows what we will see next.

[FFRacing11x]

Good to hear from you Andy.