racing gasoline

General engine tech -- Drag Racing to Circle Track

Moderator: Team

Dodge Freak
Guru
Guru
Posts: 1711
Joined: Sun Oct 21, 2007 6:56 pm
Location:

Re: racing gasoline

Post by Dodge Freak »

jmarkaudio wrote:
jeff8407 wrote:One of the other posters recommended AV Gas. I would caution against it. AV Gas is made to operate at altitude where the air is thinner and much cooler, and as a result, is a relatively "dry" fuel. It can be hard on cylinder walls. As others have suggested, ask the manufacturer.

Yep, it really beats up on those aircraft engines that drop out the sky like flies when the engines fail... What's the other one... it doesn't run well below 10,000 feet. Please. :roll:

Did anyone read the app? A 10.5 to 1 engine, wanting to add to pump gas to give it a little protection? I wonder how many thousands of successful race engines have been run on av gas over the years. Sure it may not be good or ideal for some, and the quality isn't the same as it once was, but I would much rather run it over pump gas if the cost was the same. For a 10.5 to 1 engine tune it for the fuel and it will run just fine.

I guess some feel if its too cheap, it can't be good. If it has extra octane, then a little M.M.O (or trans oil) should lube the walls--if its even a problem ? Doesn't the lead act like a lucubrate ? I knew this punk who tried to ruin a 2 stroke moped that he stole. He ran and ran it with the cheap 89 leaded octane gas they use to sell at the pump. After a few tanks with no 2 cycle oil mixed in the gas, the engine was still running. He then got to thinking and filled it up with the more expensive 87 octane no lead gas, sure enough the engine started losing power after awhile and finally stop running. That punk was then "happy" (btw, that punk double crossed me a year or so later, I should knew long ago what a jerk he was--to everybody)
rookie
Guru
Guru
Posts: 1530
Joined: Sat Aug 18, 2007 1:48 am
Location: In the woods

Re: racing gasoline

Post by rookie »

Strange Magic wrote:VP makes a product called "Red" it's 100 octane. It will be perfect for your application, and it's cheap compared to all the fuels you listed.
Do they even sell that any more? as a VP dealer I would not recommend and my suppler does not even offer it...If you can get their Round Track in your area it is a 107 and is very good.
Has Anything You've Done Made Your Life Better?
Strange Magic
Guru
Guru
Posts: 1716
Joined: Sun Dec 03, 2006 1:14 am
Location: New York
Contact:

Re: racing gasoline

Post by Strange Magic »

Have you used the red before? What makes you suggest that you would not reccommend it? Have you tested engines on it?
strangemagicperformance.com
Strange Magic Camshaft Technologies
Decisions on parts and advise should not be based on how much money a company can pour into marketing. This is a common mis-conception in the industry.
Truckedup
Guru
Guru
Posts: 2728
Joined: Mon Jan 21, 2013 2:41 pm
Location: Finger Lakes

Re: racing gasoline

Post by Truckedup »

You guys have to remember this is a air cooled vintage bike engine with 1930's Hemi head design.These things are more likely to detonate on 10.5 static compression than a wedge head water cooled engine.Back in the 1960's Sunoco 260 was ok with around 11-1 compression in these engines.I think that would be about 102 octane with today's ratings??? I would like leaded fuel...there is a small airfield nearby....
I don't want to over octane the engine...I did contact VP fuels but they haven't replied yet.
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
stealth
Guru
Guru
Posts: 1391
Joined: Fri Jun 30, 2006 9:37 am
Location:

Re: racing gasoline

Post by stealth »

Some good info on AV gas. No opinon one way or the other, just thought this was good info to know if thinking about using AV gas. written by, and thanks to
Tim Wusz
76 Products Company



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.
User avatar
jmarkaudio
Vendor
Posts: 4222
Joined: Wed Sep 26, 2007 11:26 am
Location: Florida

Re: racing gasoline

Post by jmarkaudio »

That's actually the best description from someone with a working knowledge of fuels I have seen. No BS.

The fuel most will find is the 100LL, and like ANY fuel you use ithe fuel system must be tuned for the fuel and engine it is run in. Most will need to add a jet or two to make it work decent. As far as the aromatics, this is most likely toluene or a combination of it and other aromatics. A similar fuel would be VP C16, obviously not in octane rating but that it has more aromatics in the blend. With C16 this is to be able to withstand the added heat of combustion a forced induction engine sees. What it also means is that it doesn't vaporize at lower temps seen with some of the racing fuels, so it may not be ideal for some cases. However for the bike in question I don't see any reason adding it to pump gas will have anything but positive effects over straight pump fuel with the lead content and increased octane. Jet as needed for best performance.
Mark Whitener
www.racingfuelsystems.com
____

Good work isn't cheap and cheap work can't be good.
cuslog
Pro
Pro
Posts: 375
Joined: Tue Apr 13, 2010 9:08 pm
Location: BC, Canada

Re: racing gasoline

Post by cuslog »

I've been using the 100 LL.
I'm 4 jet sizes over what the carbs came from the factory with (2 x 850 mighty Demons) and my wideband 02 meter is telling me I'm at about 12.5 AFR.
tsanchez
Member
Member
Posts: 191
Joined: Mon Jun 20, 2011 5:57 pm
Location:

Re: racing gasoline

Post by tsanchez »

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
David Redszus
Guru
Guru
Posts: 9633
Joined: Tue Nov 27, 2007 9:27 am
Location: Chicago
Contact:

Re: racing gasoline

Post by David Redszus »

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.
Trick brand was produced by Phillips 66 at their Philtex plant as a private label blend for a West Coast customer.
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.
Phillips 66 produced base stocks that were sold to race fuel blenders (including VP and 76), by their specialty chemicals division. They also produced certification and calibration gasolines for the automotive mfgs and remains as the highest quality producer of race gasoline in the country. But not for long.
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.
The shelf life of AVGAS is much better than pump gas and race gas. ASTM D910, which defines the properties of AVGAS requires the use of an anti-oxidant additive. Unfortunately, this additive produces excessive combustion deposits.
Racing Gasoline does not have these light end hydrocarbons needed for idle and starting, hence the reason race motors start and idle poorly.
While this may be true for some race gasolines, it cannot be stated for all race fuels. In addition, additives are available to tailor the fuel to specific operating conditions.
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.
The properties of AVGAS are not substantially different than pump gas in this regard. While the high octane may mitigate against detonation, it has NO effect on pre-ignition.
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.
The distillation curves are indeed similar but not identical. AVGAS has lower high ends to minimize engine deposits. The distallation curve does NOT control the speed of the burn across the combustion chamber; that is controlled by temperature and turbulence. The distillation curve will affect the ignition delay period and total burn time but not burn rate.
The LEAD (TEL) added to AV Gas is to increase the octane rating only.
Octane ratings for AVGAS are not very high, much lower than most race fuels. At octane levels of 100 or below, the ratings are the same as pump gas. At higher values they are called Performance Numbers and are given in grams of TEL that must be added. Example: 100/130, means a lean (stoich) rating of 100, and 130 means that 1.28 grams of TEL have been added to each gallon.
AV Gas is not formulated for High Altitude. and will have very little, if not any performance differences vs racing gasoline.
Well, actually it is. AVGAS contains a small amount of ethylene glycol (anti-freeze) to prevent gas line freeze at the temperatures experienced at higher altitudes.
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.
Not true and no longer true. The oxygen content of a fuel, either pump gas or race gas, does not contribute to enhanced performance, as long as the stoich value of that fuel is the same. Most fuel blenders will adjust the fuel recipies to obtain consistent stoich values. Virtually, all metropolitan areas and most states now require the use of oxygenated fuels (ethanol), not just the Peoples Republik of Kalifornia.
Advancing timing on your motor will definitely help with AV Gas and Race Gas due to its slow burn characteristics
. Not true. Will depend entirely on the specific blend and engine state of tune.
Remember this...OCTANE is a measure of a fuels ability to resist detonation/preignition.
Not true as described above.
The higher the Octane number, the slower the fuel burns.
Not true by any means and never has been.
Technically speaking 87 Octane fuel will develop more power than 118 Octane fuel.
Not true. All hydrocarbon based fuels produce almost identical BTUs/lb air. Octane rating bears NO relation to heat production.
With this said, you should see gains in throttle response and HP by mixing commercial fuel and AV Gas/Race Gas.
Not true unless AVGAS is being added to low octane pump gas in a higher compression engine. But then it would be more beneficial to run straight AVGAS rather than a blend with pump gas (which is inconsistent junk). Better yet, use the proper grade of a premium race gas designed for your specific engines requirements.
Bottom line... use the most consistent fuel you can find and create horsepower by moving as much air as possible though the combustion chamber.
Moving as much air as possible is only the first step in the production of power. Now it is necessary to evaporate the fuel, ignite it timely, and burn it completely. Otherwise, you have simply created a large displacement fuel pump, in and out of the engine.
Truckedup
Guru
Guru
Posts: 2728
Joined: Mon Jan 21, 2013 2:41 pm
Location: Finger Lakes

Re: racing gasoline

Post by Truckedup »

Reading info on VP and Sunoco websites......Generally speaking a high rpm engine needs a fast burning fuel with enough octane to resist detonation.Faster burn fuels have a lower specific gravity.... For VP leaded fuel that would be C12...A reply to this thread mentioned C12....
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
pdq67
Guru
Guru
Posts: 9841
Joined: Thu Mar 04, 2010 8:05 pm
Location:

Re: racing gasoline

Post by pdq67 »

Fwiw, Sunoco 260 was what the 12.5 to 1, 427 L-88 and the Max Wedge, 13 to 1(?) MOPAR, CR'd engines ran way back then.

Like I said earlier, buy some KEMCO 130 Lead Supreme and be done with it if you can't get E85.

pdq67
User avatar
BrazilianZ28Camaro
Guru
Guru
Posts: 3939
Joined: Mon Feb 09, 2009 10:52 pm
Location:

Re: racing gasoline

Post by BrazilianZ28Camaro »

E85 would definitelly cool things down on that air cooled engine, and never detonate with 10.5 CR.
'71 Z28 street strip car
Pump gas All motor SBC 427
3308 lbs-29x10.5 Hoosiers
NEW BEST ET
1.38 60' / 4.05 330' / 6.32@111.25mph

https://www.youtube.com/watch?v=99p13UK ... ture=share
BlackoutSteve
Expert
Expert
Posts: 812
Joined: Wed Jan 18, 2006 6:53 am
Location: Melbourne, Australia.
Contact:

Re: racing gasoline

Post by BlackoutSteve »

jmarkaudio wrote:
jeff8407 wrote:One of the other posters recommended AV Gas. I would caution against it. AV Gas is made to operate at altitude where the air is thinner and much cooler, and as a result, is a relatively "dry" fuel. It can be hard on cylinder walls. As others have suggested, ask the manufacturer.

Yep, it really beats up on those aircraft engines that drop out the sky like flies when the engines fail... What's the other one... it doesn't run well below 10,000 feet. Please. :roll:

Did anyone read the app? A 10.5 to 1 engine, wanting to add to pump gas to give it a little protection? I wonder how many thousands of successful race engines have been run on av gas over the years. Sure it may not be good or ideal for some, and the quality isn't the same as it once was, but I would much rather run it over pump gas if the cost was the same. For a 10.5 to 1 engine tune it for the fuel and it will run just fine.
I blended premium 92 with AvGas for years. Nothing adverse at all, and saved a heap as the cost of VP down here was easily double the price..
So long as you're aware that AvGas' octane ratings are for Take-off and Cruise and not Motor and Research, so 100/130 is not 115 (R+M)/2. However, most Av's (R+M)/2 is around 100-104 from what I found out. Also be aware that AvGas generally has a lower RVP (Reid vapor Pressure) for use at higher altitudes, (low flying piston engines.. -not 40,000 foot jets), so it may not vaporise so well in cold climates and/or at sea level. This was never an issue when blending, or when I ran it at 100% a few times at the track in summer. :)

Woops, just realised there's a page 2 of this thread.. :P
Post pictures, or it didn't happen!
Runit
Pro
Pro
Posts: 435
Joined: Mon Dec 26, 2011 10:10 am
Location:

Re: racing gasoline

Post by Runit »

I'd always thought the AV gas rating numbers were for the octane at differing engine opperating conditions. Like Motor and Research octane. Now it's said in this thread that the second number is grams of lead per gallon times 100. Which explanation of the numbers is correct?
David Redszus
Guru
Guru
Posts: 9633
Joined: Tue Nov 27, 2007 9:27 am
Location: Chicago
Contact:

Re: racing gasoline

Post by David Redszus »

Runit wrote:I'd always thought the AV gas rating numbers were for the octane at differing engine opperating conditions. Like Motor and Research octane. Now it's said in this thread that the second number is grams of lead per gallon times 100. Which explanation of the numbers is correct?
The grams of TEL added to isooctane is correct. The details are spelled out in ASTM D-910, which defines the requirements for AVGAS.
Post Reply