Halo

I'm sure this has been discussed before, but a search revealed nothing recent so here goes...

Where do you guys get higher than 91 octane (not including race tracks) around SF? Back in the day Union76 used to sell 93 but I haven't seen that stuff in a while?

S2-Raw

76 Station On Woodside in Redwood City.

$4.19 per gal for unleaded 100 octane.


And it doesn't do Jack.

Feezy

do you notice any difference running that stuff?

DaRKCrow

:Correction:

The S2000 have a memory system that records your driving habits and fuel input. It takes time for it to memorize or adjust to changes.

Someone local have put a full tank of 100 oct in the car, he did not feel any difference until last 2 bars on the gas.

It does make a difference, but you must let the car adapt to the changes.


DaRKCrow

LATEOTT

Wow, it's interesting you're asking this right now. I have been actually looking for a good deal on Toluene. Gas is so F'n expensive now that I was thinking of increasing my octane by adding toluene, now that it's cost is not THAT much more than a gallon of gas. From what I've read about one gallon per tank (~10%) would take it up to 94 octane, and two gallons (~20%) would take it to to about 96 octane. I'm still shopping around, but it should make it come out to be less expensive, and might be more effective, than buying racing fuel.

Yes, your car will take some time to adapt. Best thing you can do is pull the ECU fuse so it resets to default parameters. You basically delete the history and it will adjust to the new fuel.

CrazyPhuD

I'm sorry I have to disagree here, so unless you have numbers this statement doesn't hold water. Why? It's very likely this is the placebo effect. Think about it.....you just put $50 of gas in your tank, hoping that it's going to make your car faster. So you're going to be looking at every time to say..."Is my car faster?" eventually you'll trick yourself into thinking that it is, when it fact it isn't just because you WANT it to be faster.....

The reality is high octane is for one reason, anti-knock resistance. The higher the octane the less likey you are to detonate. The only case where high octane gas will help you generate more power is if your engine is knocking. If your engine starts knocking then the ECU will pull timing. The F20C and F22C are designed to run on 91Octane gas. in 99.9% of driving they should not be knocking. You will not notice any difference running higher octane gas, except in rare cases. If you run FI 100 octane provides some safety to your engine, if you don't it's a waste of money.....

CrazyPhuD

http://www.pontiacstreetperformance.com/ps.../Mythsgas1.html

SuperDyu

yup gas itself wont make the car faster... being able to safely put in more boost/compression does, the high octane just saves you from any catastrophic things happening.

LATEOTT

The way you say it is true: higher octane fuel cannot, in itself, boost performance (with fixed engine parameters.)

But the overall premise that higher octane fuel does not allow for added performance on high compression engines is wrong . It's just a little less direct.

In the right engine (F20C, for example) higher octane can allow the engine to run, knock free, with advanced timing and more aggressive fuel mapping, whereas lower octane fuel cannot. Under those more agressive parameters the S2000 will have better performance.

I think the big question here is: What is the fuel octane level that allows an F20C to run under its most agressive parameters (where it will offer the most power under hard acceleration in the heat).

I think we know that 87 Octane is too low. Is 91 too low? Or is it just perfect?

Seems like it makes sense to see if bumping the octane a little can allow engine parameters that provide better performance (once the ECU has been reset).

Everything I have read says that the octane boosters you buy at Pep Boys might increase octane by a couple tenths, so that's not even worthwhile and definitely not cost effective.

But you can add straight toluene or xylene (aromatics that are already in gas anyway) to boost octane more dramatically. If you get it for $5 a gallon it only increases your per gallon fuel cost by $0.50 which is way better than racing ruel at almost any venue.


I think it's worth experimenting with. But yeah, I agree that the results could be very subjective and subject to the placebo effect.


And just because higher octane doesn't help a Pontiac doesn't mean it won't help an S2000.

CrazyPhuD

[QUOTE]Originally posted by LATEOTT
The way you say it is true: higher octane fuel cannot, in itself, boost performance (with fixed engine parameters.)

But the overall premise that higher octane fuel does not allow for added performance on high compression engines is wrong . It's just