Racing Fuel, Worth An Experiment?
 

my mechanic mentioned that a certain sunoco station sells racing fuel. is it worth experimenting with?

will it do damage to my car? it's 100 octane correct?

i'm curious what FE can be achieved on straight gas, but will this curiosity kill the cat(car)?

Just make sure that it isn't leaded race fuel. I think only the 104+ octane blends have a risk of being leaded but if it isn't than have at it.

I've considered adding white gas like a fellow member had mentioned to lower the octane level of my fuel. I have always been under the impression that you see the best economy from a fuel that has the lowest octane level the engine can run without becoming a diesel lol

When I had my motorcycle carbs worked on the person who did the work put racing fuel in it. You sure had to be careful on the throttle just cracking it open and the bike was gone. 30 years ago it would have been fun if I didn't kill myself. The extra power was the only benefit and on an 1100 I don't need that much extra power. A friend of mine that is a mechanic said running fuel with that high of octane in a stock engine could burn the pistons. That information came from a person who has been doing mechanic work for over 40 years. Just something I wanted to throw out there. I'd talk to someone who knows before trying it.

yep, my mechanic said i'd get quite an explosion using it! :D

thought about filling only 1/2 race fuel to spare the pistons.

how do you lower the octane of a gas?

By mixing it with lower octane fuel...
When I worked for a fuel station when we wanted midgrade we'd order 1,000 gallons 87 octane and ~200 gallons 93 octane to make 89 octane.

-Jay

Burn holes in the pistons with high octane gas? I think the mechanic had this backwards: using LOW OCTANE fuel in a high compression engine will burn holes in the pistons from detonation. NOT the other way around. Also, contrary to popular belief, high octane fuel does NOT have a higher BTU content than lower octane fuels. The BTU content of all hydrocarbon fuels is about the same (more or less). High octane fuel will not give you more power UNLESS you have high compression, and the ECU retards timing if pinging occurs with lower octane fuel. So there really isn't anything to be gained by using racing fuel in a car with 9:1 compression. Unless, of course, you just like to brag about using race gas in your Metro or VX. Hell, even my B18C5 CRX (which has 11:1 compression) does not seem to benefit from using 100 octane gas over just plain old 91 octane gas.

I should add, though, that it IS possible for fuel to cause a hole to be burned in the piston if the volatility is low. This COULD be a problem with SOME racing gasolines. Specifically, it is possible that fuels designed for turbo or supercharged engines were not made with volatility in mind (since the hot intake charge in a forced induced motor will pretty much vaporize everything). But you will be fine with the 100 octane stuff you can buy at the pump (although you won't notice a difference). Anyway, a fuel of low volatility can cause a lean condition (by not completely vaporizing), which will lead to detonation AND give you lots of oxygen to burn away aluminum from the piston. This COULD be what the mechanic is talking about. But even if it is, it is not the high octane itself that is the problem.

Absolutely no benefit and besides the huge cost of running it, it can only have a negative impact. You're not going to be able to burn the fuel fast enough so most of it is going to come out your exhaust pipe.

Are you running super advanced ignition timing? (If so, why?) Is your car pinging on 91 octane?

I'll be curious to see your results as well...we have, of all things, an Alta Dena milkhouse with a gas station attached...they just started selling 93 and 100 octane "Streetblaze" fuel. At 6.99/gallon for 93 octane, and 7.59/gallon for 100.

StorminMatt and suspendedhatch are correct here, you won't see any increase in fuel economy as both high octane and low octane contain the same amount of energy. high octane just resists detonation much better. so it would be great if your engine was modded with a silly high compression ratio - more compression = higher power and efficientcy. lower octane would ignite under the pressure potentially causing severe engine damage.

some race engines are designed like this and/or they use turbochargers at stupid high boost levels. compressing an extra 30-40 psi into your cylinders really raises the pressure in there. regular fuel would just detonate so race fuel is required. some will just lower the boost with a boost controller for lower grade fuel and bump it up for the track or when they are running the higher octane.

Yup, about the only place you would see improvement is if you had a turbo set up. Basically a way to change compression ratio on the fly.

My friend used to set his Turbo to 22-23psi on 93 Octane, but now and then would get 100 and increase it to 28psi. Running 100 at 22psi would do nothing, at 28psi you have a bit more 'compression ratio', that is more O2 forced into the engine in the same size space and then you get a use out of it.

100 Oct is the highest without lead, the only other Octane I've seen is 110 and was definately leaded. There's also Aircraft fuel, I've heard you can get it from most all small airports, I think it's 104 Octane and unleaded, but not sure, only guys I saw using it were some people on their heavily modified rally cars. Running 100 shouldn't hurt anything, but running leaded will destroy your cat pretty quickly, this is second hand info, but I was told it chemically reacts with the platinum in the cat and renders it inert.

If you want to experiement with high octane fuel why not try E85? Or 1/2 mix E85 and E10 for starters. I've thought about doing this, but without a turbo I'd have to custom build a 13-15:1 engine which would be infeasible.

thanks guys. i realize higher octane will not yield higher FE. my thought and hope was that i could test gas w/out ethanol.

i changed vehicles just as E10 was getting integrated locally, so i was not able to test the theory of higher FE w/ straight gas.

Ah interesting, I wonder how 100 Oct reacts to fuel warmer and the other old 'tricks' that supposedly only the 'older' fuel blends without alcohol worked with. When I think of 100 Octane I feel like I'm using pure gasoline without additives from the 60s or something (it's a nerousis I have :p), but I suppose it probably has just as many detergents and things to decrease the volatility. Anyone know?

As for E10, look at Jay's thread on testing Ethanol content, you may be running E6 and just might find a spot with E0 to properly perform your test with.

Or get a 15 gallon drum, put 2 gallons of water in the bottom, 13 gallons of gas and let the alcohol separate out, and siphon off the "pure" gasoline...

-Jay

Higher octane won't help the FE and will also make the car feel sluggish.

I run Sunoco 100 oct and 109 oct unleaded in my Fiero on a regular basis. I run a different tune and boost level when running race gas. The car is very sluggish running race gas on a 93 octane tune.

ok, i'm gonna fill up on sat or sun. if that station still has race fuel, i'll test it 50/50 with 87 octane. any other warnings, please make it known.

This is starting to remind me of that episode of Family Guy where Peter puts airplane fuel in his pickup and imagines that he's flying...

https://familyguy.wikia.com/wiki/Airport_'07/References

Don't laugh. My uncle put jet fuel in his Ford Windstar thinking it would run better. It ran like crap. I think it would have run better on kerosene. :rolleyes:

-Jay

100 octane fuel isn't going to be leaded for the cost that is talked about.

Some of the 100 octane unleaded fuels are designed to be spec fuels. Often, they don't perform as well as even an E10 blended fuel. I used to sell racing fuel to racers and shops, and there was a shop I worked with that would cut some of the common unleaded fuels with unleaded pump street gas to develop more power. That was in a time when we were getting MTBE as an oxygenate in pump gas, and MTBE is also an oxygenate in oxygenated leaded and unleaded racing fuels.

Final trick about racing fuels is this: If it's coming out of an unsealed container, I won't use it. Transportation in different tanks, storage, etc. corrupts the fuel with what was in it prior and with contaminates, water, rust, etc. So, it's a crap shoot.

You don't want to use a leaded racing fuel in anything with a cat. It'll trash it in addition to plating the O2 sensor. Cat will get ruined far quicker.

Finally, how a fuel is built/combined is different from one brand to another. Octane can be developed from different combinations of chemicals. Not just the chemical, but even the order in which it is added. This affects specific gravity, which affects carbureted engines a lot more than fuel injected vehicles, Reid Vapor Pressure, the initial tune, final tune, and the end output. Yeah, one fuel of 110 octane can have more power than another manufacturer's 110 octane fuel in the same engine.

As far as I know, Jet A is a kerosene-based fuel, while Jet B is a kerosene and gasoline mixture. Jet B is used primarily in cold climates. In theory, a car that burns gasoline should at least run somewhat on Jet B, but not Jet A (running Jet A in a gasoline engine would be like filling your tank with diesel). However, it would probably (among other things) ping REALLY badly, since jet fuel does not need to (and, therefore probably woudn't) have a high octane rating. On the other hand, a diesel engine should run fine on Jet A. And MANY airports run fuel trucks and other such vehicles on jet fuel in order to simplify things in terms of needing different kinds of fuels.

I would venture to say that since he dumped some in the tank, even if it was A to begin with, it ended up being B from mixing with the fuel already in the tank. It was a bright idea he had one day with the help of his friends Jose Cuervo & Jack Daniels. ;)

-Jay

my apologies, that sunoco station no longer has race fuel. no experiment.:thumbdown:

One of the Petro Express stations close to where I live in NC has racing fuel. If you have any of them around you might check them out. Petro Express here sells Texaco gasoline.

My opinion
 

My opinion it will not help you any to run the higher octane unless you are pinging (which you may not even be able to tell) Higher octane fuel does not make better horsepower or mileage but it allows you to use higher compression or boost.
Now if your computer is retarding the timing for bad fuel and you put higher octane gas in there it will help both performance and mileage. I will not hurt anything except your wallet to run the high octane fuel unless it has lead in it. I do not see how 100 octane could hurt any motor but if you have a motor built for 100 and you run it with 87 it will definalty hurt performance, mileage and even the motor. Clear as Mud?

If you can get Jet-A cheap, you can try mixing 20-33% with E85 :D

It's "easy" to run on kerosene btw, all you need is about 5 headgaskets, or to slip your timing belt by a tooth so you've only got about 6:1 dynamic compression ratio... hmmm wonder if you could stack A LOT of sparkplug spacers ....... just kidding really, you'd need to find about another 40-50cc with them... though if you had a 8:1 motor, it might be plausible to find another 10cc like that... and it might run eventually, if you wrapped the fuel line round the manifold, and did the flaming rag in the intake trick to start it....