[GreekMaverick]

Hey guys, got a Q, Can I use Aviation Fuel in a Vehicle? (335i?)
Not to be confused with jet fuel,

100/100LL Octane Rating.....Someguy from work told me that he buys few gallons everytime he goes to the track for his SRT4 and slices his time consistenly by 0.7/sec, never had a problem...?, I am kinda skeptical to say the least....!

Any opinions?

[kevkaz]

Originally Posted by GreekMaverick

Hey guys, got a Q, Can I use Aviation Fuel in a Vehicle? (335i?)
Not to be confused with jet fuel,

100/100LL Octane Rating.....Someguy from work told me that he buys few gallons everytime he goes to the track for his SRT4 and slices his time consistenly by 0.7/sec, never had a problem...?, I am kinda skeptical to say the least....!

Any opinions?

Leaded fuel will damage cats and who knows what else.

[GreekMaverick]

Originally Posted by kevkaz

Leaded fuel will damage cats and who knows what else.

So i thought....Thx.

[Cadillac Johnson]

Leaded fuel will kill your cats and eventually your o2 sensor.

Other than that, it's actualy better for your motor as it has additional lubricating properties.

As far as airplane fuel, there's no reason to run the risk of using it over race fuel engineered for cars. It probly works fine, but it's not the smartest thing to do.

He probly just wants to feel special so he can tell chicks "Yeah baby, it's an SRT4, I run airplane fuel in her, standard gas isn't JDM."

[GreekMaverick]

Originally Posted by Cadillac Johnson

He probly just wants to feel special so he can tell chicks "Yeah baby, it's an SRT4, I run airplane fuel in her, standard gas isn't JDM."

Thx CJ

[rideelement247]

I'd watch race/fuel and fuel additives. Many contain a chemical called xylene, which is a chemical used during tissue processing in hospitals. Trust me, I work in one. Someone a couple of years back got it in her eye and it dissolved the eye in a few seconds. REALLY nasty stuff. They say as long as the fuel doesn't sit in your tank for more than a week you should be alright. The shorter time span that it is in there, the better. i.e. I wouldn't fill her to the brim with it. Run maybe a 1/4 to 1/2 tank of gas like that or mix it with pump gas.

[Neema]

i just pumped a full tank of 100 octane fuel from a local gas station here.......im TT and down pipe back exhuast equiped and i dont feel a thing on the butt dyno. Probably becuase unless you have an ECU tunned to understand and utilize 100oct. fuels........its pointless for more HP right?

[Nyulak]

Correct, if your ECU isn't adjusted for 100 octane, you aren't going to achieve much of anything. There may even be a decrease in performance.

[RedGT3]

Originally Posted by Boost_Nation

i just pumped a full tank of 100 octane fuel from a local gas station here.......im TT and down pipe back exhuast equiped and i dont feel a thing on the butt dyno. Probably becuase unless you have an ECU tunned to understand and utilize 100oct. fuels........its pointless for more HP right?

Try disconecting the battery. This way you can reset the store learning (timing)in the DME.

[1clean335i]

white exhaust tips ..... Ran it in the lexus several times. C16 that is... I heard aviation fuel was cheaper though

[BoostedBMW]

I guess if you are thinking of running leaded 100 octane fuel, then you might as well just run leaded race fuel that has 116 octane. Now all you need is a tune for it so your not wasting your money on the gas and fouling out your o2 sensors.

Some gas stations sell 100 octane unleaded so I would just go with that.

[Former_Boosted_IS]

Originally Posted by Nyulak

Correct, if your ECU isn't adjusted for 100 octane, you aren't going to achieve much of anything. There may even be a decrease in performance.

Huh? Decrease in performance? 100 octane fuel is no different than 93 octane fuel if you are running identical boost. We really need to put this as a sticky, but octane is nothing more than a measurement of its resistance to detonation, i.e. pre-ignition. The higher the octane, the more resistant it is to detonation. Why is that important? Well for two reasons:

1. You can run higher boost on race fuel (higher octane) than pump fuel because the fuel is more resistant to detonation. That is because the fuel will not ignite before the spark plug fires even with the higher IAT temps.

2. You can run a leaner A/F ratio because of its resistance to detonation. The leaner A/F makes more power and heat, but more heat in the cylinder can be tolerated because the fuel is the higher octane.

Just remember without a different tune or without a way to raise boost, your race fuel gives you nothing.

[e90AW335i]

Originally Posted by Former_Boosted_IS

Huh? Decrease in performance? 100 octane fuel is no different than 93 octane fuel if you are running identical boost. We really need to put this as a sticky, but octane is nothing more than a measurement of its resistance to detonation, i.e. pre-ignition. The higher the octane, the more resistant it is to detonation. Why is that important? Well for two reasons:

1. You can run higher boost than on pump fuel because the fuel is more resistant to detonation. That is because the fuel will not ignite before the spark plug fires even with the higher IAT temps.

2. You can run a leaner A/F ratio because of its resistance to detonation. The leaner A/F makes more power and heat, but more heat in the cylinder can be tolerated because the fuel is the higher octane.

Just remember without a different tune or without a way to raise boost, your race fuel gives you nothing.

Good info....

[Nyulak]

I didn't say will, I said may. This is dependent on several factors, like the type of fuel used to get a higher octane rating. If you use E85, the octane rating is higher, but the energy content is lower. The basic point is that if you don't need higher octane for an application, don't use it.

The differences in octane are more evident in conditions that create a greater chance of detonation. If you aren't running your car hard for a fuel-up, say you're just cruising to another town on a trip, don't spend too much on a higher octane fuel. If you are going to track, higher octane may be used to ensure the safe operation of your engine of extended periods of high-load use.

There are some benefits to premium fuel that come with the detergents that are added to help keep the engine clean. These extra chemicals may not be available at lower grades, so a premium fill on an occasional basis may be good. May not matter as much on a direct-injected engine considering the valves don't coke with fuel, since the fuel spray is direct to cylinder and not at the top surface of a valve. However, you still want to keep the rest of the fuel system clean.

[de.abeja]

Originally Posted by rideelement247

I'd watch race/fuel and fuel additives. Many contain a chemical called xylene, which is a chemical used during tissue processing in hospitals. Trust me, I work in one. Someone a couple of years back got it in her eye and it dissolved the eye in a few seconds. REALLY nasty stuff. They say as long as the fuel doesn't sit in your tank for more than a week you should be alright. The shorter time span that it is in there, the better. i.e. I wouldn't fill her to the brim with it. Run maybe a 1/4 to 1/2 tank of gas like that or mix it with pump gas.

Xylene will NOT disolve human tissue in seconds that is absurd. I don't know what sort of work you do but it has nothing to do with medicine, and as a nurse I despise it when people vaguely attatch themselves to my field. Statements like yours violate the trust that is given to those in charge of providing health care for others.

Xylene is the main ingredient in 'Goof-Off' and many other stain removers, it is a drycleaning solvent and kissing cousin to Tolulene which we all know from gasolines past. While I would not drink it or put in in my eye as I sure it would not be very good for you, It will dry your skin out, and very well may cause cancer but it won't make your eyes disolve.

[valerun]

Originally Posted by Former_Boosted_IS

Huh? Decrease in performance? 100 octane fuel is no different than 93 octane fuel if you are running identical boost. We really need to put this as a sticky, but octane is nothing more than a measurement of its resistance to detonation, i.e. pre-ignition. The higher the octane, the more resistant it is to detonation. Why is that important? Well for two reasons:

1. You can run higher boost on race fuel (higher octane) than pump fuel because the fuel is more resistant to detonation. That is because the fuel will not ignite before the spark plug fires even with the higher IAT temps.

2. You can run a leaner A/F ratio because of its resistance to detonation. The leaner A/F makes more power and heat, but more heat in the cylinder can be tolerated because the fuel is the higher octane.

Just remember without a different tune or without a way to raise boost, your race fuel gives you nothing.

on #1 - minor nit but igniting before the spark is pre-ignition, not detonation. Different phenomena. Pre-ignition much worse for the engine.

On aviation fuel - still don't have an answer - has anyone tried to run 100LL in their catless 335's? As a private pilot, I have easy access to 100LL at ~$4.5 a gallon which is much cheaper than $6.5/gallon 100 octane race gas around here...

V

[Ilma]

Originally Posted by Former_Boosted_IS

Huh? Decrease in performance? 100 octane fuel is no different than 93 octane fuel if you are running identical boost. We really need to put this as a sticky, but octane is nothing more than a measurement of its resistance to detonation, i.e. pre-ignition. The higher the octane, the more resistant it is to detonation. Why is that important? Well for two reasons:

1. You can run higher boost on race fuel (higher octane) than pump fuel because the fuel is more resistant to detonation. That is because the fuel will not ignite before the spark plug fires even with the higher IAT temps.

If you are igniting before the spark plug fires then you have major problems.

Detonation happens after the spark ignites and causes a secondary pressure wave that disrupts the normal combustion process:

FYI......Detonation is the spontaneous combustion of the end-gas (remaining fuel/air mixture) in the chamber. It always occurs after normal combustion is initiated by the spark plug.....not before.

Initial combustion at the spark plug is followed by a normal combustion burn. But for some reason, likely heat and pressure, the end gas in the combustion chamber spontaneously combusts and creates a secondary ignition point within the same timing window. The key point here is that detonation occurs after you have initiated the normal combustion with the spark plug.

Pre-ignition is defined as the ignition of the mixture prior to the spark plug firing. Anytime something causes the mixture in the chamber to ignite prior to the spark plug event it is classified as pre-ignition.

The two are completely different and abnormal phenomenon and are caused by different reasons.

[GaryS]

Originally Posted by Former_Boosted_IS

Huh? Decrease in performance? 100 octane fuel is no different than 93 octane fuel if you are running identical boost. We really need to put this as a sticky, but octane is nothing more than a measurement of its resistance to detonation, i.e. pre-ignition. The higher the octane, the more resistant it is to detonation. Why is that important? Well for two reasons:

1. You can run higher boost on race fuel (higher octane) than pump fuel because the fuel is more resistant to detonation. That is because the fuel will not ignite before the spark plug fires even with the higher IAT temps.

2. You can run a leaner A/F ratio because of its resistance to detonation. The leaner A/F makes more power and heat, but more heat in the cylinder can be tolerated because the fuel is the higher octane.

Just remember without a different tune or without a way to raise boost, your race fuel gives you nothing.

Dinan says the Dinan tunes and stock tune adapt to higher octane gas by advancing the timing and leaning the mixture for more power. So "we also recommend using unleaded racing fuel whenever you do a track day." I think I remember the Dinan rep told me the adaption takes less than one lap.

[techlogik]

Yeah, as a former pilot, 100LL is purple. It is LOW LEAD. Which will burn up your CATs like others have said.

Find a place with unleaded race...I know it is a bit more expensive...unless you don't care about your CATs.

[Bme30]

not all aviation fuel is leaded, and it should be fine for your car. the best part about some if not all aviation fuel it does not have the ethanol it it.

[newBMWownr]

Originally Posted by techlogik

Yeah, as a former pilot, 100LL is purple. It is LOW LEAD. Which will burn up your CATs like others have said.

Find a place with unleaded race...I know it is a bit more expensive...unless you don't care about your CATs.

100LL is Blue. 115/145 AVGAS is Purple (and is no longer available except in batch production for events like the Reno Air Races).

Also low lead refers to the reference fuel AVGAS 100/130 (dyed green and also no longer available). There's still 1.2 to 2.0 grams of TEL per gallon in 100LL: enough to foul your cats, O2 sensors and spark plugs.

AVGAS also has a fixed vapor pressure (no summer or winter formulations). I'd guess not an issue in a DI engine, but maybe.