Lose HP With Race Gas?

[ltr450rider]

So I was going to get some race gas for my Pismo trip this weekend and was looking for a place to buy it, but then I came across this little tidbit of information that I have never heard before. I have met Alan from CT Racing once before and he seems like he knows what he is talking about. Apparently he says unless your motor is tuned for race gas, you can actually lose horsepower if you are running it in a motor tuned for 91!!!!

http://ctracing.com/race_fuel.htm

My LTR is a stock motor and I have run race gas mix in it before, seemed to run a little harder. Any motor builders here have any thoughts on this before I waste my money...

[FE135]

This is true. 110 octane vrs 91 octane fuel are the same for energy output. One burns slower than the other for higher compression. If you use race gas in a stock motor setup for 91, you would need to change the timing to compensate. Waste of money.

[Adam @ GTP Off Road]

i know running race gas if it's not needed can certainly make your wallet have less power... lol

not sure about your actual question though.

If i didn't need it, i wouldn't run race gas though. I would like some clear gas (93 Octane and no ethenal) here in Vegas though.

[raspadoo]

have a street bike, when I burn race gas at the end of the season it does not run near as well as it does on 91, burn rate is too slow

[ltr450rider]

I was always under the impression that running race gas in any motor would add HP. I am certainly not new to the world of internal combustion engines and I had never heard this before. I will continue to run 91 then.

I have seen an addative that you are supposed to run in ethanol mix, I guess ethanol is not good for high performance ATV/MX motors. Since Cali is all 10% ethanol these days, I might try some of that addative.

[mineurbiz]

Even if your motor is setup to run one type of race fuel and you change, you will need to tune for that fuel. But like stated above, if you have a stock compression motor, your not going to see a benefit from running race gas, will probably lose performance.

[bulldogz400]

Even if your motor is setup to run one type of race fuel and you change, you will need to tune for that fuel. But like stated above, if you have a stock compression motor, your not going to see a benefit from running race gas, will probably lose performance.

^ This. You'll get the most power running the lowest octane fuel that still prevents detonation. Unless the fuel has an additive, or is an Oxy fuel (MRX01, U4.4, etc, etc) you're not gaining anything...except a lighter wallet.

[1320]

This is why we run 87 in stock motored drag busa's. They make more power. There is actually more power to be made on lower octane fuel, as long as it doesnt need the octane to prevent detonation.

The burn rate is different from the octane rating, but they often go hand in hand. There is a 91 octane race fuel marketed also....I think mostly for drag bikes. I havnt used it in years now. I always get a kick out of someone saying they run 100 for more power. Bulldogz400 is exactly correct.

[Adam @ GTP Off Road]

I ran 87 in the Raptor for the first part of it's life and only started running 91 this summer after i got the Dyno tune, and changed the Timing with the programmer. The manual stated 87, but the intake lid said 91. My Outlaw 525 says it requires 91. Just dropping to 87 would save a little gas money, and I can use gas pump discounts when i fill the truck to fill the cans. the raptor is still on stock compression, and I never noticed an issue before.

[turbo_bruce]

if you want some more power use pump gas and put some Propylene oxide in it you will have to up jet a bit but you will see a power gain. its been used for years for cheating in all forms of racing . i like using it fun to play with