Racing gas question!

[Tripper]

A friend & I were talkin' about racing gas & I'm not sure what he is saying is true. He says racing gas has less power per gallon than regular gas. He says it does have higher octane but doesn't have as much power. Can this be true?!?

BoB

 

[Gregster]

It is harder to ignite and has a slower burn rate , therefore you don't preignite the fuel with higher compression , diesel fuel has a very low octane rating so it will ignite under combustion , but that's what you want there . At least that is what I have always been told

 

[Sam_Fear]

A friend & I were talkin' about racing gas & I'm not sure what he is saying is true. He says racing gas has less power per gallon than regular gas. He says it does have higher octane but doesn't have as much power. Can this be true?!?

BoB

Maybe by a miniscule amount? Just seems to me, one wouldn't spend thousands upon thousands of dollars on a HP motor just to dump low energy fuel into it?

 

[RPM]

We actually dyno tested gas at one time. These were 1 cyl tractor pull motors. The racing gas makes less power with low compression, it burns too slow. A motor with 8:1 compression made more power with 89 octane than it did with 116 octane. Everything else was the same only changed the fuel. It was not a big difference in these 1 cyl motors, only something like 3/4 of a HP. On a stock 10 hp motor that was almost 10%...So 10% on a 350 could be quite a big loss on a stock low compression engine.

 

[Sam_Fear]

That makes sense. It's not that it has less "power", meaning to me, stored energy, but that it won't MAKE as much power in a engine not specifically designed for it.

 

[Gearhead10]

some guys around here have made their stockcars run on e85 cuz its accually higher octane than race fuel, makes more power and burns cleaner. When I raced we used to mix 110 race fuel with regular gas and made some serious hp out of a 9:1 flat top motor.

 

[bob w]

Maximum horsepower will be achieved by using the lowest octane fuel that the engine runs well on. Meaning, no ping or detonation.

 

[Tripper]

Thanks guys! I'm gonna try some race gas for grins & I'll tell ya what I think!

BoB

 

[Sniper]

Also, octane is not a tangible item, it's not a liquid you can pour in the tank. It's a form of measurement, a low octane rated fuel will autoignite with a moderate compression. Add a additive such as heptane or an ethanol and the octane rating goes up because the fuel is now more punky and can be squeezed even tighter (more compression) before it will autoignite. The increased compression is the key to more power produced. So, use a low octane fuel in a high compression engine and you get a lot of expensive junk in short order, the detonation will trash the engine. High octane rated fuel (punky stuff) in a low compression engine and it will produce less power than if it were run on reg fuel, as was stated earlier. So the original statement of "race fuel has less power".... if used in a low compression engine, yes.

 

[Tripper]

So the original statement of "race fuel has less power".... if used in a low compression engine, yes.

I guess that doesn't apply to me then... I don't have any low compression motors! [ddd[ddd[ddd

BoB

 

[Pookie Bros]

diesel fuel has a very low octane rating so it will ignite under combustion , but that's what you want there . At least that is what I have always been told

Diesel has an octane number of about 15-25. The reason for this seemingly terrible number compared to the ones we're used to from gasoline is the fact that diesel is combusted in a totally different type of engine. Diesel has low volatility, low knock resistance, yet high energy per volume. Because of its low knock resistance, diesel should not be used in a gasoline engine as it will destroy it very quickly and efficiently.

Generally speaking, diesel fuel ignition quality is not measured in octanes, as these are a unit for gasoline. A similar reference value, but for diesel, is the cetane rating. The higher the cetane number, the easier the fuel ignites when injected into an engine. The cetane number is determined by an engine test using two reference fuel blends of known cetane numbers. The reference fuels are prepared by blending normal cetane (n-hexadecane), having a value of 100, with heptamethyl nonane, having a value of 15. The higher the cetane rating, the higher the fuel's propensity to knock! Choosing a very high cetane number will not make the car run better, but using a fuel with too low cetane number may prevent the engine from starting or running.

 

[Rat'l Trap]

So the question about octane vs. power has been explained pretty well here.
I have a different question, presumably about high octane fuel. When at the dragstrip, I love the smell of what I guess is race fuel. What makes that sweet smell in the air when a high-powered car goes down the track? [dr

 

[jfg455]

could be a car running on methenol. Therte is no mistaking that smell. You can pick it up on a turbo car that is just running an 18% replacement under boost.

CAM2 up here smells sweet

 

[rainman]

Some Racing fuels are scented. Lot of guys I know run a fuel that smells like grape.

 

[Outlawracer]

Alcohol (Methanol) Does have its own smell. Ran it in my Sprint Car. Some guys put in an additive that smelled like grapes. At first it started some contraversy cause some thought it was a fuel booster and it is not. Just for smell. When you run Alcohol you should also run a top lube otherwise it is hard on valve guides and seats. Alcohol is very dry compared to gas. I always ran Klotz upper engine lube and worked well.
E-85 is at least 85% alcohol but unless you have a vehicle designed for it your vehicle will not run too good. I run it in my pickup alot cause it is cheaper and does not give the arabs as much money but lately around here there is only about 10 cents a gallon difference. Was about 60 cents. In my truck it does lose a little pulling power and about 50 miles per tank full on E-85 so it is making sense to start running gas again with the little difference in price.

 

[Skullnbones]

Stock engines with low compression will not benifit from racing gas. When you get into power adders and higher compression things change.

 

[ANNAMEL]

Ran latemodel high compression and made more power with 75% racing fuel and 25% amaco gold. Did run some 190 ethanol and made good power with the the h20 converting to steam and increasing HP. Kinda like water injected.

 

[busch]

A few buddys would run air plane fuel in there 4x4s 10/1 comp 1/2 tank of gas mixer up make the old stock truck pulls interesting, he who cheats best wins