Staff member
when I was much younger there used to be 100- 130 octane labeled or rated AVGAS available at the local small plane section of the local air port for about twice what standard high test pump gas cost, we would purchase 15 gallons in 5 gallon jerry cans and mix in the fuel with 2-3 OZ of marvel mystery oil per jerry can, and use that in our race engines, it worked very well because it was high lead and high octane... the last time I went was decades ago, back in the 1970s,
While there are some high octane formulations of avgas, airplanes over the last 40 plus years have trended to lower compression ratio, so the "100-130 octane " avgas is not very common any more, in fact its damn rare!.

Also avgas is formulated to vaporize when it's cold with low barometric pressure. Not what you want on the ground. but they refused to sell it to auto racers,
at that particular time for some reason, at the time.
I was told it was due to terrorists ,using avgas , thats TOTAL B.S.


http://www.monstermarketplace.com/army- ... -jerry-can






History of AVGAS Grades

Avgas is gasoline fuel for reciprocating piston engined aircraft. As with all gasolines, avgas is very volatile and is extremely flammable at normal operating temperatures. Procedures and equipment for safe handling of this product must therefore be of the highest order.

Avgas grades are defined primarily by their octane rating. Two ratings are applied to aviation gasolines (the lean mixture rating and the rich mixture rating) which results in a multiple numbering system e.g. Avgas 100/130 (in this case the lean mixture performance rating is 100 and the rich mixture rating is 130).

In the past, there were many different grades of aviation gasoline in general use e.g. 80/87, 91/96, 100/130,108/135 and 115/145. However, with decreasing demand these have been rationalised down to one principle grade, Avgas 100/130. (To avoid confusion and to minimise errors in handling aviation gasoline, it is common practice to designate the grade by just the lean mixture performance, i.e. Avgas 100/130 becomes Avgas 100).

Some years ago, an additional grade was introduced to allow one fuel to be used in engines originally designed for grades with lower lead contents: this grade is called Avgas 100LL, the LL standing for 'low lead'.

All equipment and facilities handling avgas are colour coded and display prominently the API markings denoting the actual grade carried. Currently the two major grades in use internationally are Avgas 100LL and Avgas 100. To ease identification the fuels are dyed i.e. Avgas 100LL is coloured blue, while Avgas 100 is coloured green.

Very recently a new Avgas grade 82 UL (UL standing for unleaded) has been introduced. This is a low octane grade suitable for low compression engines. It has a higher vapour pressure and can be manufactured from motor gasoline components. It is particularly applicable to those aircraft which have STCs to use automotive gasoline.

http://www.centennialofflight.gov/essay ... Tech21.htm


I am going to attempt to address the controversy of aviation gasoline verses racing gasoline for use in race cars. Some racers use aviation gasoline which is fine for some applications but does have shortcomings. There are several grades of aviation gasoline (avgas) that we must identify before going any farther.

1. Avgas 80/87: this product is used in low compression ratio aircraft engines, contains little or no lead, is red in color, and should not be used in any automotive engine due to a low motor octane number of about 80.

2. Avgas 100/130: this product that can be used in some automotive engines. It has both research and motor octane numbers slightly over 100. Avgas 100/130 is green in color, contains four grams of lead per gallon, and is becoming harder to find.

3. Avgas 100 LL: the LL stands for "low-lead" which means two grams per gallon, low compared to the avgas 100/130 that it was designed to replace. It has research and motor octane numbers very similar to the 100/130 product previously discussed. The color is blue. This product sometimes has a high level of aromatics which can contribute to lazy throttle response and dissatisfaction of the consumer.

4. Avgas 115/145: this product was developed for high performance piston aircraft engines used in world war II and in the Korean war. It is very hard to find anymore due to lack of demand although it is of very high octane quality. The color is purple.

The remainder of this discussion will assume that our basis for comparison with racing gasoline is avgas 100/130 and/or 100 LL since they are both available and have acceptable octane quality for limited applications. When the word "avgas" is used, it will refer to avgas 100/130 or 100 LL.

Avgas is less dense than most racing gasolines. Instead of weighing about 6.1 to 6.3 pounds per gallon like racing gasoline, it weighs 5.8 to 5.9 pounds per gallon. The racer must compensate for this by changing to richer (larger) jets in the carburetor when changing from racing gasoline to avgas.

The other major difference is octane quality. Avgas is short on octane compared to most racing gasolines. Many racing engines with "quick" spark advance curves or with no centrifugal advance have more spark advance at low rpm than avgas and some racing gasolines can handle. The result is detonation, especially during caution periods in circle track racing because all of the spark advance is "in", rpm is low, and part throttle air fuel ratios are too lean for the operating conditions. If the driver does not "work" the throttle back and forth, pistons can be "burned" which melts away part of the aluminum piston material. Inadequate octane quality is one of the quickest ways to destroy an engine. Pistons can be severely damaged during one acceleration where detonation is present and the racer may not know what is happening until it is too late.

For maximum performance and power from a racing engine, racing gasoline will normally provide better performance than avgas. Avgas can be a good gasoline for some applications, but since most racers do not know the octane requirement of their engines, they would be better off with a "real" racing gasoline that will give them the overall resistance to detonation that they need to protect their investment. If someone has spent from $15,000 to $50,000 or more on their racing engine, it is foolish to cut corners on gasoline be sure you have a gasoline with adequate octane quality.
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Grumpy Do You have a source where you bought your JERRY CANS ?
Been looking around to purchase a few for myself.
Like the Vintage WW2, Korean War, Vietnam style.
Army & USMC.
Are the small caliber bullet tough ?
Don't want the Repop chuna stuff.
GOOD STUFF. :mrgreen:
I found Real Jerry Cans Grumpy.
Going to buy them.
Post link later.
Made in Great Britian.
Will fill Nozzle also.
No Chuna crap.
heres something I found elseware
100ll Avgas ! what I found the hard way!
I think some of you may know this or are just not full of tinkeritis like my self !
This was copied from another forum. Interesting read for avid uneducated tinkerers like my self.

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 bitchin 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

Can I run AvGas in my vehicle?
AvGas is short for Aviation Gasoline. AvGas is of interest to motoring enthusiasts because of its availability, octane rating and low price compared to commercial race fuels. AvGas might seem an obvious choice but closer study raises some doubt.

AvGas LL100 stands for "Low Lead 100 Octane". TEL (Tetra-ethyl-lead) is added to raise the octane. When used in a motor vehicle this fuel will leave a lot of lead deposits in the motor. 100LL has a high lead content (0.5 grams per litre), even higher than leaded race fuels. The deposits left when TEL(lead) is burned are corrosive and damaging to valves, valve guides, valve seats and cylinder heads. Lead deposits will also block oxygen(lambda) sensors and catalytic converters and foul spark plugs even after only a short use. Also, 100LL has a chemical package added to make it perform at high altitude, and that isn't the best thing for motor vehicle performance here on the ground.

AvGas is blended for large-bore, long-stroke, low RPM engines which run at high altitude. While AvGas' higher octane is useful, smaller-bore, shorter-stroke, high RPM engines will perform better on racing fuel or high quality octane boosters. AvGas has lower volatility so when used in proportions higher than about 40%, part-throttle drivability and cold starts may be compromised. AvGas has a lower specific gravity so it will require a change in air-fuel ratio calibration for the engine to perform at its best. LL100 is blended with a high percentage of aromatics causing reduced throttle response which is not an issue with an aircraft engine but certainly an issue in a high-performance automotive engine. These high levels of aromatics will also damage rubber components in automotive fuel systems such as fuel lines, fuel pump seals and injector washers.

The sale and use of AvGas is heavily-regulated. Most aircraft fuel dealers refuse to put AvGas into anything other than an aircraft fuel tank. There is a legal grey area that has some vendors willing to dispense AvGas into "approved" containers if they believe the end use of that AvGas is fueling an aircraft engine. This loop-hole is how some may obtain AvGas for automotive use. Because AvGas has no taxes and duties on it, use on public roads is illegal and if found could result in your vehicle being impounded.


The Bottom Line:
Avgas may be suitable for some race cars that don't have catalytic convertors or oxygen sensors and are rebuilt often enough that the TEL(lead) build-up is not an issue. For other applications use an unleaded race fuel or a good quality octane booster.
I am going to have some spare $$$ this weekend.
I think I will go out & buy 5-10 gallons of 100 LL AV Gas.
Use in the 63 Pontiac.

Read last night on Facebook Racing groups 110 VP Racing Gasoline is now $12.50 per gallon in many parts of the USA.
AV Gas is $6.50 per gallon reported.
Not sure how much it is local till I go and buy it.

I used to buy 100 LL for just $1.99 a gallon.
Even when it went up to $2.99 a gallon it was OK.

E85 looks good.
Its real hard to get LS Corvettes to start and run on it in the fall here in Illinois.
Recall from the Race shop.
No Vertex Magneto & those Racing coil packs guys say are the best are not Hot enough to light off right when cold.
What is the shelf life of avgas?


Bill Albrecht, who has a heli-pad and hangar in his backyard, recently installed a 2,000-gallon avgas tank. His question: “”What is the shelf life of avgas?””

Bill Albrecht, who has a heli-pad and hangar in his backyard, recently installed a 2,000-gallon avgas tank. His question: “”What is the shelf life of avgas?””

The short answer is that, under most conditions, the shelf life of avgas is about one year. If you are a commercial operator, this is the end of the discussion.

For a private pilot, however, there are several points to consider. First, there is a large margin of safety in the one-year storage life of avgas. The main concern when storing fuels is oxidation and subsequent formation of gum. Once the fuel starts to form gum, it can cause problems in the entire fuel system. I’ve checked numerous avgas samples after two years or even more and found no degradation, with the samples meeting all specification requirements. The samples will last even longer if the container is blanketed with nitrogen or stored in a colder climate.

The second point is that the one year shelf life applies to avgas and not auto gas. If a pilot is using auto gas, he should make a serious effort to use all of the fuel supply within six months of purchase.

So if avgas is good for one year, how long can you store lubricants? Let’s start with engine oils. The specifications generally state that the manufacturer must guarantee a product will meet physical property limits for at least three years. Here again, I’ve tested oils after five and 10 years ? from sealed containers ? and found them to meet the spec. There was a small amount of additive settling after 10 years, but the oil was still on spec. I’ve also checked samples from open drums after three to five years and found them to be on spec except for a amount of moisture dissolved in the oil. This is not a serious problem if your engine is running with a proper oil temperature and can evaporate the moisture on the first few flights. However with a low usage aircraft, especially one with an oil temp below 160?F, the moisture can contribute to increased rust activity in the engine.

The mil spec for aviation greases calls for the manufacturer to guarantee that the product meets the limits for at least three years. This is for a product in a sealed container. The problem with grease is that much of it is used from an open-top container, which is generally open to the atmosphere. Here the product is prone to absorb moisture. This can be a problem because many of the applications for these products do not get to a temperature high enough to boil off the moisture. This can lead to increased rust activity and decreased component life. Therefore, it is important to always smooth out the top surface of the grease to limit the surface area exposed to air. I also have found numerous containers that were not properly covered. Many of these samples contained an excessive amount of dirt and foreign matter which could decrease component life. Greases should be stored in a dry place with the lids tightly sealed.

Ben Visser is an aviation fuels and lubricants expert who spent 33 years with Shell Oil. He has been a private pilot since 1985. You can contact him at Visser@GeneralAviationNews.com.
I was recently asked to help start a 1969 corvette that had been in storage for over 30 years ,
the first thing I strongly suggested was to replace ALL the fluids like oil and fuel, coolant ,
brake fluid and all the related filters, fuel,oil, air etc.
obviously the battery was long ago in need of replacement,
and I was rather curious if the coolant and rust and corrosion was going to be a major issue,
the guy wanted to simply pour in 5 gallons of fresh fuel, the new owner was purchasing it from the former owners heirs ,
I wanted to drain and flush the fuel system,the guy selling the corvette said that the former owner always used avgas.
the engine was not original, I ran the vin and block numbers they did not match, the engine was a 350 hp 396. ( I think its from a camaro)
and after looking in the fuel tank with an LED light that was rather obviously mandatory.
he ordered a new fuel tank and fuel pump and we flushed the fuel lines, amazingly the engine appeared to be in decent shape,
I had removed all the spark plugs and squirted a few table spoons worth of marvel mystery oil into the cylinders,
and we had replaced the oil filter and filled the crank case with a 6 quart load of shell 10w30 and a quart of MMO,
and rotated the engine a dozen times without the plugs installed, before we tried to start the car.
once the plugs were pulled the tires and checked the brakes,they looked reasonable, so we re-installed the wheels ,we pressurized the tires
(they were in need of being replaced after sitting 30 plus years )
I would not suggest driving the car with them and backed the car out of the garage,
we turned on a garden hose next to the car in the drive way in-case things went badly,and hooked up a timing light.
removed the plug wires from all the spark plugs , but the #1 cylinder and set the timing
it smoked like a mosquito spray truck ,once the other spark plugs were connected, for about 4-5 minutes,
but held good oil pressure and amazingly the carb did not leak fuel and seemed not phased with a 30 plus year vacation,
we had partly filled the fuel tank with high test gas and two bottles of fuel system cleaner and injector cleaner,
to hopefully remove and ancient crud,in the carb or fuel lines and temporarily added an added second in-line fuel filter before the carb inlet.
, and once it cleared the chamber oil, it idled decently