Jeff Taylor

Yeah, you bring up a good point...tuning with pump-grade octane is probably a good idea... I wouldn't want to have to re-tune for 93 when I get back on the street.

However, running "race gas" or higher octane at the track is definitely not a bad idea. When racing without an automatic data-logger, you usually can't pay attention to your gauges, and therefore don't always know when you're pushing your car past its limit or not. I'd rather have the higher octane in the tank as a fail-safe method to prevent expensive engine damage.

Higher octane will usually not hurt your performance, nor should it improve your performance if the engine is properly tuned (so that it doesn't knock and pull ign timing). So why not run it at the track?

Jeff

bill strong

I run 110 Sunoco Leaded in mine all the time now. I don't consider mine a pussy car either. There is a huge difference in power on pump gas, it will only rev to 7500 on 93 pump, but with 110 it goes right to 9600 where my max power is.

Is it expensive? I buy it by the drum, so I save a ton.
I really think you guys with air filter and big mufflers and OBD / ODBII wont have to worry about adding the max gas.

JS4KIKZ

Detonation is a BITCH! Usually use 93 octane on the dyno, but on occasions, I'll do a mix. Its called PREVENTIVE MAINTINANCE

HighPSI TSi Guy

man where in c-ville do you find sunoco?

bill strong

$5.25 a gallon, bring your own cans...
There is a motorcycle shop on 10th street and West Main St. about a block east from the Corner.

IT IS LEADED FUEL.

HighPSI TSi Guy

ah ok.. i didn't realize it was the leaded stuff.. i was thinking it was the pump stuff they have at sunoco stations that you can get for like $2 a gallon

Rguy

"I'd stick with normal octane, because the higher the octane, the harder it is to burn, and it is also cooler, thus cooling your exhuast, making spool times a little slower..etc."

Have any proof of this? The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites.The compression ratio (remember, boost affects compression too) of your engine determines the octane rating of the gas you should use. The higher your compression or boost levels, the more and more you must use higher octane fuel to resist pinging or knocking. No "cooling" or anything happens at all. Tuning your car on race gas or mixed gas is BAD, when you go back to normal pump gas octane ratings your effectively putting yourself closer and closer to a pinging situation.

marshall

i think doing an initial tune (ie 'rough tuning') on high octane is a good idea. especially in certain cases that are out of the ordinary. for instance if someone were to build a saturn motor for high boost, there is really no baseline for that sort of thing. so i would start out with some C16 on the dyno because you never know what you're gonna get. one mistake at 20 psi on 93 octane and you could lose some rather expensive parts.

if i were tuning my car on a dyno i would be interested in tuning on 110+ because that is what i put in the car when i race it. i'm rather uninterested in getting the perfect 93 octane tune because i don't race on the street when i would be running 93...

marshall

Rguy

"if i were tuning my car on a dyno i would be interested in tuning on 110+ because that is what i put in the car when i race it. i'm rather uninterested in getting the perfect 93 octane tune because i don't race on the street when i would be running 93..."

But see, thats a mistake a lot of these stunnas just trying to make high HP numbers do. If you tune that way and just get up and leave without putting some safety measures in (retard timing, back off on boost, etc) your gonna get fucked when you refill with 93. Ping city. I know no one on this board would leave without the safety measures though

JS4KIKZ

but im not calling you stupid, Im just agreeing