SR71!

Like the title says, just wondering if anyone has used high octane / racing fuel with a rating of 104 or higher in a stock LT4 engine?

Are there any adverse effects that could occur using such fuel with a stock set up, or will it run like a champ?

I was thinking of getting 5 gallons to really clean out the fuel system since we have a local track that sells race fuel of varying grades.

I just know lots of you track your cars and thought someone has done this and might chime in, as I surely don't want to cause a problem by doing this without some homework.

Thanks!

pologreen1

Waste of money.

Match fuel to engine needs.

You can put jet fuel in a drag car and it won't go faster or cleaner.

You can put 110+octane in a factory car and it is the same effect. Speaking from experience I did this as a kid watching some guy with a "cool" 383 that would mix. It was was dumb, and I was more dumb to follow. If you have like 12+ compression yes, it would be needed.

My current build makes literally 4-5 times as much power as my car back then and I can still run on 91-93 pump gas.

I think the newer fuels have "cleaning gents" more octane does not clean a fuel system.

Cleaner or buying new injectors, changing fuel filter, and fuel pump will make for a a clean out.


Your car can run on 87-93 octane and it won't help or hurt it.

SR71!

cool thanks! Ill just stick with some fresh 93 then... I just changed the fuel filter.

aklim

You will go faster at the track if your wallet is lighter. Everybody knows weight brings down the time.

If you are having dirty injectors, send them for cleaning. Results will tell you how often you may want to clean them. So if you are comfortable with say a 5% loss every 5 years, clean them then. Race fuel probably won't clean much.

If you want to do your homework, get a scanner that can datalog. See how much knock you get doing say 5 WOT runs with premium gas, run the car to empty, dump say 5 gallons of race gas and do another 5 WOT runs in similar conditions. Compare and contrast.

PatternDayTrader

Like Pologreen1 already made clear, you don't want to do that.

I would add that the c4 era cars test the knock sensor by advancing the timing until a knock occurs, a few seconds after startup. In the event the ecm/pcm cannot make the car knock, it may stop advancing the timing, or set a knock sensor code, or both.
I never personally verified this, but it is what was taught in fuel injection training by GM instructors, during that era.