100LL/race gas interesting read

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This was copied from another forum.

Key points:
-100LL is not 100 octane as we rate it for pump gas (R+M/2). It is actually ~96 octane by that measure.
-Quality and consistency is better than pump
-Shelf life is better than pump.
-Cheaper because you are not paying Road Taxes. Legally it's like running red dye... no no on the street.
-Lower Specific gravity than pump (density) means you actually run leaner with the same jetting.
-Important one here! Lower flame speed than race gas. 100LL is designed for 3500RPM operation. If you run consistently higher than that you will be spitting unburnt fuel out the pipe. Most pre-run or play cars don't spend too much time over 3500RPM

Real info on Race Gas/Av Gas...

My experience comes from 7 years as the western states representative for 76 Race Fuel, Unocals 40 hours Advanced Products course, Working personally with Tim Wusz (senior performance products Rep for Unocal, Tim was responsible for Unocals race fuel development for 30+ years). I have also met and discussed fuels/motors with just about every engine builder in every facet of racing in the western United States. I also conducted Educational Seminars at the Fred L. Hartley Institute in Brea in which we would invite Engine Builders for a tour of Unocals testing facilities and do live octane tests on any gasoline they would choose to bring to the seminar. Included in the training we would demonstrate live tests how Distillation curve, Reid Vapor Pressure, Specific Gravity, Octane Rating, F;ashpoint, etc are conducted and the importance of these numbers. Some of you will remember me from contingency with my 76 Racing Gasoline hospitality trailer in the 1990's.

Through the 50's, 60's, 70's and 80's Av gas was the base product used for most racing "gasoline". VP, f&L, Turbo Blue, and Trick all used AV gas as the base product. They would buy a tanker (8000 gallons of Av Gas) than add other hydrocarbons/TetraEthylLead (TEL) to the base, drive around the block stopping and accelerating the truck/trailer until they felt the product was mixed well. Obviously this was not science, but it worked for most racers only because most racers use a higher rated octane than they actually need.

In the mid to late 1990's VP graduated to buying there own base product and do there blending of products in a much better fashion. Turbo Blue and Trick have since been bought Sunoco and are blended by Sonoco. Trick was purchased by Phillips 66 and has continued to be blended by Phillips 66.

The only two companies I am aware of who "cracked" there own base product is Sunoco and 76. And as we all know, 76 race fuel is no longer available, leaving only one true manufacturer of Racing Gasoline....Sunoco.

AV Gas has a MOR (motor octane rating) of 96, R+M/2 rating of 100, and ROM (Research Octane Rating) of 106.

AV Gas is lighter than racing gasoline thus more fuel/larger jetting is required. Jetted correctly you should not experience a lean burn at WOT.

I would not use AV Gas as a cleaner. The amount of TEL (2 grams/gallon) and other hydrocarbons makes it extremely carcinogenic. Same goes for all other racing gasolines.

Shelf life is NOT better. The reason pump gas won't last as long is because street gas has extremely lightend hydrocarbons to help your car start and idle. Racing Gasoline does not have these light end hydrocarbons needed for idle and starting, hence the reason race motors start and idle poorly.

Av Gas is NOT designed for low RPM motors. AV Gas is designed to not detonate/preignite causing detination. This would be the same design as race fuel. If you compare the "distillation curve" of AV Gas to Race Gas, you will find they are almost identical. The "distillation curve" controls the speed of burn across the combustion chamber.

You will only "spit" gas out the exhaust pipes if you run to rich or include a supercharger/turbocharger on your engine and "overdrive" the blower. Example would be the [censored] flames you see at the starting line of a drag race on normally aspirated engines and the long flames you see on all "blown" engines.

The LEAD (TEL) added to AV Gas is to increase the octane rating only. All heads these days have harden valve seats. There is no need for lubrication of the valve seats. All engines have come with harden seats since the late 60's.

AV Gas is not formulated for High Altitude. and will have very little, if not any performance differences vs racing gasoline. On the other hand, commercial grade fuels (87, 89, 92) will definitely enhance your performance due to the commercial fuel being oxygenated. The Oxygen enhancers added to commercial fuel is only for California Smog laws.

Advancing timing on your motor will definitely help with AV Gas and Race Gas due to its slow burn characteristics. On the other hand, be careful if your running commercial grade gasoline, more timing can cause detonation/preignition quit quickly.

AV Gas does not go BAD faster. It is extremely consistent. The MOR is only 96, whereas Sunoco Purple or VP C12 is 104. A rating of 96 is good for up to 10:1 on Steel heads and 12:1 on Aluminum heads with water cooling. Air cooled motors run much hotter.

Buying a higher octane for a $20-50K motor is the cheapest insurance available.

Remember this...OCTANE is a measure of a fuels ability to resist detonation/preignition. The higher the Octane number, the slower the fuel burns. Technically speaking 87 Octane fuel will develop more power than 118 Octane fuel. With this said, you should see gains in throttle response and HP by mixing commercial fuel and AV Gas/Race Gas. You now have some light end Hydrocarbons for throttle response and heavy hydrocarbons/TEL for detonation resistance.

Bottom line... use the most consistent fuel you can find and create horsepower by moving as much air as possible though the combustion chamber.

I have no reason to be bias here as I have moved on to much greener pastures. See you on the race course.

Good Luck,
Steve Poole
 
I've used 100LL on my NINJA and it went to 11k rpms, so the speed flame isn't that slow, IMO. And 2 (two) grams of TEL for 1 gallon? I thought it was 0.2 grams per gallon in a 100LL Avgas.
 
I would have to say, the analysis is spot on, to the limits of my knowledge. The thing to remember is, leaded fuel is only legal to use in aircraft. If the Feds chose to make an example of you, it could be serious. Their favorite method of exracting a pound of flesh is to fine you $10k PER VIOLATION! This can add up to real money, and this is treated as an infraction, so the ability to fight it is limited.

Also, we all have forgotten the amount of maintenance eliminated when lead was removed from fuel. Spark plugs being a prime example, but certainly not the only one. Lead gets into stuff, and does not remove itself. I doubt that modern automotive oils have the needed ability to remove lead from ring packs and pistons. Mobil had a very bad experience with a foray into Aero oils, with lead sludge packing pistons and rings, in aircraft engines. Use at your own risk.
 
I'm not sure who in the heck would put 100LL in a road car. But I hope they know 100LL is dyed blue, not red. If it's red I'd like to know where you find it!
 
Originally Posted By: SEMI_287
I'm not sure who in the heck would put 100LL in a road car. But I hope they know 100LL is dyed blue, not red. If it's red I'd like to know where you find it!


It is a reference to on road/off road diesel.
 
Originally Posted By: 4wheeldog
I would have to say, the analysis is spot on, to the limits of my knowledge. The thing to remember is, leaded fuel is only legal to use in aircraft. If the Feds chose to make an example of you, it could be serious. Their favorite method of exracting a pound of flesh is to fine you $10k PER VIOLATION! This can add up to real money, and this is treated as an infraction, so the ability to fight it is limited.

Also, we all have forgotten the amount of maintenance eliminated when lead was removed from fuel. Spark plugs being a prime example, but certainly not the only one. Lead gets into stuff, and does not remove itself. I doubt that modern automotive oils have the needed ability to remove lead from ring packs and pistons. Mobil had a very bad experience with a foray into Aero oils, with lead sludge packing pistons and rings, in aircraft engines. Use at your own risk.


When I used I've got discarted fuel from a container. You know, when pilots do test fuel for contaminans, we need to drain a few from each drain pulg on every fuel tank and also from the strainer. You get 1/10 of a gallon sometim from each airplane. Some pilot still use the old pour down on the floor technique, since it evaporates, so quickly. Our hangar suggest a more environment friendly manner to discard it, in a container. Some FBO's and airplane rentals use it in their mower and other equipment, some burn it, some send it to recycler, some donate. It's not a business ... At the end of a busy day, a big hangar could have a discarded extrated fuel as much as 2 gallons to recycle. Once I got very low on fuel, that was in 1999, I recicled some in my bike. And that's how I end up using, I dind't buy it from the fuel truck to "use on the street".
And it's not harmfull to use in a bike that has no catalist converter, as it isn't very high ZDDP oils.
 
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My references for contraindications for use did not include the CC, (Though that would be CATastrophic) but are still valid.......MC or PCMO is no longer up to the task of removing lead deposits from rings and pistons, not to mention the deposits and wear on the spark plugs. One of the best things ever done for increased engine life/decreased maintenance was the elimination of lead from fuel.
 
I use it in all my outdoor power equipment, 2 & 4 stroke. I love everything about it except the yellow lead coating it puts on the plug and muffler. I'm not so concerned about the lead, everyone in LA breathed it for decades and not everyone died or when crazy.
 
Originally Posted By: 4wheeldog
I would have to say, the analysis is spot on, to the limits of my knowledge. The thing to remember is, leaded fuel is only legal to use in aircraft. If the Feds chose to make an example of you, it could be serious. Their favorite method of exracting a pound of flesh is to fine you $10k PER VIOLATION! This can add up to real money, and this is treated as an infraction, so the ability to fight it is limited.

Really? I thought that the prohibition is against leaded gas being used on street vehicles. A vehicle that only sees track or off-road use can still use leaded fuel. Apparently some farm equipment still uses leaded gas.
 
Originally Posted By: y_p_w
Originally Posted By: 4wheeldog
I would have to say, the analysis is spot on, to the limits of my knowledge. The thing to remember is, leaded fuel is only legal to use in aircraft. If the Feds chose to make an example of you, it could be serious. Their favorite method of exracting a pound of flesh is to fine you $10k PER VIOLATION! This can add up to real money, and this is treated as an infraction, so the ability to fight it is limited.

Really? I thought that the prohibition is against leaded gas being used on street vehicles. A vehicle that only sees track or off-road use can still use leaded fuel. Apparently some farm equipment still uses leaded gas.


It is illegal to dispense leaded Avgas into anything other than an aircraft. And, I believe aviation gas is the only legal dispensation for manufacture of leaded fuel. If there is any other legal source for leaded fuel, it is news to me.
 
Any fuel or oil distributor will sell you canned LEADED race gas. AV gas is legal to sell for racing purposes, no plane required. Almost all airports think you have to put in a plane only. If you call the main office of the av gas retailer they will usually be glad to sell you fuel for non aviation use. I've had the airport guys not believe me and call in to check. I love to drive my truck onto the runway and fill up a few cans!
 
Originally Posted By: 4wheeldog
Originally Posted By: y_p_w
Originally Posted By: 4wheeldog
I would have to say, the analysis is spot on, to the limits of my knowledge. The thing to remember is, leaded fuel is only legal to use in aircraft. If the Feds chose to make an example of you, it could be serious. Their favorite method of exracting a pound of flesh is to fine you $10k PER VIOLATION! This can add up to real money, and this is treated as an infraction, so the ability to fight it is limited.

Really? I thought that the prohibition is against leaded gas being used on street vehicles. A vehicle that only sees track or off-road use can still use leaded fuel. Apparently some farm equipment still uses leaded gas.


It is illegal to dispense leaded Avgas into anything other than an aircraft. And, I believe aviation gas is the only legal dispensation for manufacture of leaded fuel. If there is any other legal source for leaded fuel, it is news to me.

Really. VP Racing sells a lot of leaded fuel for track racing and off-road use. They have specific categories where they list their leaded fuel for use in ATVs, snowmobiles, personal watercraft, and powerboats. They even have a "vintage" leaded gas that they warn is for show cars that is not street legal.

http://www.vpracingfuels.com/vintage
 
Originally Posted By: 4wheeldog
Originally Posted By: y_p_w
Originally Posted By: 4wheeldog
I would have to say, the analysis is spot on, to the limits of my knowledge. The thing to remember is, leaded fuel is only legal to use in aircraft. If the Feds chose to make an example of you, it could be serious. Their favorite method of exracting a pound of flesh is to fine you $10k PER VIOLATION! This can add up to real money, and this is treated as an infraction, so the ability to fight it is limited.

Really? I thought that the prohibition is against leaded gas being used on street vehicles. A vehicle that only sees track or off-road use can still use leaded fuel. Apparently some farm equipment still uses leaded gas.


It is illegal to dispense leaded Avgas into anything other than an aircraft. And, I believe aviation gas is the only legal dispensation for manufacture of leaded fuel. If there is any other legal source for leaded fuel, it is news to me.


Chucle. If you drain for contamination checks and sometimes you suspect there is, you shouldn't put it back on the fuel tank, or should you? It could be contaminated since it is in the lowest part of the fuel tanks where the drain plug is installed. If it has a drop of water, it will be collected in the plug valve and will be spilled out, when you drain. Illegal is to put back possible watery fuel, made from condensation, back in the system.
 
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High octane doesn't burn slower. It burns pretty much the same speed as lower octane does.
So that's not quite right.

Cool story though.
 
Originally Posted By: 4wheeldog


It is illegal to dispense leaded Avgas into anything other than an aircraft. And, I believe aviation gas is the only legal dispensation for manufacture of leaded fuel. If there is any other legal source for leaded fuel, it is news to me.
There's a gas station that sells 100LL around here. Big sign right on the highway. I suppose you could land a plane on that road but I haven't heard of it.
 
Quote:
There's a gas station that sells 100LL around here. Big sign right on the highway. I suppose you could land a plane on that road but I haven't heard of it.


Where???
 
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That article contradicts itself quite a bit... not all truths there for sure.

Anyway, can any of you shed some light for me as to how to convince my local little airport to sell me 100LL for use in something other than a plane? We (my son and I) race motocross bikes with some hi perf 2 strokes and we simply can't afford VP fuels at $70 for a 5 gallon pail!

I've called The local airport here a few times now and they will not dispense the fuel into anything other than aircraft...
 
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