Aviation fuel vs race fuel???

[440forPOWER]

Does anyone out there use aviation fuel in their race car instead of racing fuel? I seem to remember an
article about how aviation fuel was hard on parts due to lack of lubricants but cant remember much more
of the article. I am just trying to save a few bucks this year on fuel and was considering the switch to
aviation fuel but dont want to risk any unnecessary damage. Also is there any performance difference?
THANKS and any help would be greatly appreciated

[r3racing]

Don't even consider it. If you want to get a real reaction, call Chuck Senatore at Muscle Motors and tell him you are considering running aviation gas in one of his motors. You will definitely get an ear full.

[rumblefish360]

LOL, I have heard the same thing. Not a good choice to run Av-fuel in a car. Your right, something about it.

[shannon]

Aviation fuel has a high octane rating like race gas but does not burn as quickly. Therefore it will not perform as well as the quicker burning race gas at a high rpm.

340 party

[HankL]

This has been extensively discussed before.
See these posts for example:

http://www.moparchat.com/forums/show...light=Gasoline

http://www.moparchat.com/forums/show...light=Gasoline

http://www.osbornauto.com/race2avgas.htm

[Keith W]

I have to give my opinion.If Aviation fuel was corrossive, less lubricity, all that crap, the they wouldnt sell it for people to lock up their airplane motors and crash.people who say that AV Gas is bad, are stupid in the fact that they dont study this, they are going by what people say! I know labs ,both independent, and federal.90% of airplanes that run AVgas(not Jet A)stay below 5,000 ft. thats lower than some tracks out mid west. Now, if airplanes have iron cylinder walls, and aluminum pistons, and carburetors with rubber tipped needle and seats,where is the difference.
So to answer you question, if you have 11.5:1 or less compression, you go right ahead. Dont even worry about it. if it was bad, would they let it in airplanes? just ask yourself that. muscle motors are greasemonkeys anyway. Go to thier shop once, then, you believe me.

[Pierre Amado]

i live in a small town in western canada and you can't get racing fuel around here and it's a pain in the ass to order it all the time . for being a small town we have towns around us and there are probably about 400 racers around here and all everybody runs is av-gas and nobody seems to have any problems with it. but a year ago i started to work at a methanol plant and started experimenting with that, it worked really good, but i also get to work with m.t.b.e(methyl tert butyl ether) its an octane mixture in gasoline but when you have it in bulk with the proper mixture it can raise the octane 4-6 points and make quite a boost, look it up . i think this is the website- www.geocities.com/motorcity/9185/page.html

[djswwg]

Keith W made some interesting points-does anyone have any other info? Around here av gas is WAY cheaper than race gas. If it works as well I'd be very tempted to use it! Has anyone ever run their car using both these fuels with no other changes and compared time slips? to me that would be the best performance indicator. As for engine damage caused by the av gas, I find it hard to believe, but if somebody has pertinent info, please pass it on.........djs PS, Keith W do you use av at the strip?

[rat roaster]

I agree it works ok. I have used it straight up and mixed. You will have to jet fatter about 3 sizes. It burns slower so your headers may glow a bit. Good race fuel will usually make more power. The specific gravity is around 707.7 Kg/m3. I use 100LL in my 440 10.5 to 1 its a street car it runs in the 11s. I keep some around the farm for the kids toys mixed 50/50 it works great in the 4 cycle honda dirt bike and really wakes up the 13hp honda (4cycle) on the go-kart .I liked the 100/130 better but I cant get it anymore. All in all it works ok and is usually cheaper than race fuel but in some applications it will make less power than race fuel. Just jet for it .

I have also used it in my 150 merc two stroke boat engine it ran great and smelled cool on the water. The guy I buy it from says it works great in snow mobile engines .

[Keith W]

I have a neighbor across the street, he has a Brand X(mustfag 5.slow) and he rns a blower,underhood that is. Its elct fuel inj, and has map sensors, Race gas will mutilate a O2 sensor. AV gas usually wont.AV gas has a lower lead content than race fuel, but more than Pump Gas!!
i know fuel pretty well, have 2 chemist in the family.
Nitro propane is a great additive for pump gas. Av gas ,yeah, I run it at the track, and is clearly .4 seconds faster. Makes 420 rear wheel hp in my all street Dart.

[jfs mopars]

The information I recieved from a very knowledgable manufacturer was as follows:
Aircraft octane rating systems are different than auto.
Aircraft fuels rate lower when compared against each other.
Aircraft rarely seem much over 2500 rpms and are at a steady rpm, not vary like autos.
They rate aircraft according to a rich/lean device on the aircraft.
I'll stick to quality race gas.

A trick some of the flyers are using is automotive gas.
( Go figure?)

[Keith W]

I cant say it any more plain. This is one of the most controversial subjects. As having a person in my family who is a Biochemist, and a microbiologist I have great source.
AV gas was the first race gas in Italy in the 40's-70's.Then Shell introduced a real race gas in 1957 or so.But the cheaper teams ran AV Gas with nitro propane additive.AV GAs DOES NOT burn slower. If this was true, planes would run more initial timing, they run 38 total. just like us.Real close. People say it burns slower, you getty up to 10,000 feet, no air pressure, you need a fuel that burns, Get my drift? Hope this is making sense to you guys. I hope I aint sounding like an Asshole either.

[Keith W]

Ok, they use Auto fuel for 2 reasons, easy to get, and its 41 cheaper a gallon at least here. but, you gotta get permission to even get it on most airport property. I have a buddy who has a RV4 plane, he got the permit to run car gas, he said over 6,000 ft, it sux. Go figure.

[SB Racer]

Based on experience, not on any scientific formulas or fancy calculations.
I have used Shell avgas in my racecar for three seasons now with no probs.
I have won all there is in this part of the world (scandinavia), will use it
this summer too. On winter I checked my engine inside, valve seats and all.
Not single sign of bad fuel. So in my opinion go for it and save your money.
BTW my engine has 12.4:1 C.R and takes my 2800 lbs to mid tens.

SB Racer
http://www.paalupaikka.com/racevaliant

[Gam Man]

Guys, in Australia, we have been using avgas for twenty years both in the street and at the track on street/strip type cars. In all that time, I have never seen a engine failure that could be directly attributed to the use of avgas.

Yes, its true that it is designed for lower revving aircraft engines and I've heard that its octane at higher altitudes changes b/c of it structure but if it works in the car at a cheaper price why not use it ??

You may have probs at the track if the specific gravity of the fuel does not pass tech though... something to keep in mind for your class of racing!!

[70AARCuda]

In las vegas..we can buy AVgas for 2 bucks a gallon...or racing gas for 4.50 a gallon at track...several friends and I have run AVgas for years...and years ...and years...In fact...we have tried racing gas...the gas did not run anyfaster...nothing broke cause of the AVgas...and in many cases ....if you smell it coming out of the exhaust pipes you dont know the difference....

The 360 engine had 12:1 compression with W2 heads...ran a best of 10.62 in vegas @2100 ft above sealevel...

Now the hardest part is finding it...all the small airports have been taken over by the County and they will not sell it to racers anymore

tony

[blackcuda]

I thaught you guys should know,

I have been an AMT (airplane mechanic) for seven years, so I know a little about 100LL. I have been working jets for the past three years but used to work on piston engines. A couple of things people don't know about avgas is one that it has an anti-icing agent in it so that the carburetor does not ice up at altitude. This chemical will break down some rubber parts over time. Also the octane numbers are different and the fuel changes octane numbers with temp change. That being said I used to run 100LL in my cuda, it ran great! I belive that it is way better than what you get at the pump but it is not as good as race gas. I now run VP C16. The LL stands for low lead, more like unleaded in my book! I hope this helps some of you out.
IMHO, if you can get race gas it is a better choice in a race car, But maybe if you just wanted to spray the local bully one Saturday night the 100LL would be better on your engine than the 93 crap you get at the pump...
to coin a phrase, just my .02 worth!

[Billydelrio]

Down here in SouthWest Texas, VP racing fuel was $6.75 per gallon the last time I bought some. I use exactly one gallon per round of competition in my 273 Dart. Seven or eight rounds gets expensive. AV gas is still $2.something a gallon. When my drum of VP Green is gone, I am thinking of a switch to AV gas. However, If the car is not as fast after jetting and timing for the AV gas, I might switch back to VP before I put my new engine in . In other words, I have not made my mind up yet.
Most of the guys around here have been running AV gas forever and they are all the time blowing engines up. But they are also Cevy Guys.

Billy

[Billydelrio]

Opps, I misspelled Chevy in my previous post.

[Walkercolt]

My nickles worth. I used to work for Cities Service Oil Co. and at one time we were the second largest distributer of AV fuel(largest of jet fuel). Here are some facts to think about. AV-gas has a much lower vapor pressure than race gas(less "nose" or light ends) so it won't vapor-lock at altitude. AV-gas must not contain over .005%water, to prevent carberator icing.Areo engines MUST RUN MAGNITOS and the spark advance is NEVER more than 28 BTDC, radial engines run much less advance.Aero engines are torn-down and/or re-built every 300 hours. Very,very few modern aero engines have iron barrels, most are nickel-silicon coated(like 2 stroke engines). Most Aero engines have sodium cooled valve heads, to keep seat tempertures down.Big item is aero engines run at a constant RPM, idle to max power changes the rpm less than 175RPM, some big radials only have a 25RPM range. Now AV-gas is good-stuff, especially the purple 135-150.This grade is extreamly high lead content(more than 7 grams per gallon). Mixed with a some good unleaded, it's a good motor fuel for racing, although plugs will quickly foul, and jetting will have to be adjusted. The last time I bought purple av-gas, it was over $4.00 a gallon(when and if you can get it) I can buy race gas for $3.75(102 lead-free) I buy 112 octane unleaded Phillips in a 5 gal can for $28. I can get their leaded racing fuels for only a little more. You can make it work, and in your area there maybe a big price difference. I like the fact that race gas is the same can to can, and I can get the octane and lead requirements I want easily. You pays your money and takes your chances.

[66Dart_GT]

I would like to clear up a few misconceptions, 1. I have not seen an aircraft engine that runs “38 total timing like us” most aircraft engines are timed 22 to 28 degrees. 2. Water in the fuel does not cause Carburetor Ice, Water in the fuel causes engines to quit because they wont run on water, atmospheric conditions cause Ice to form in the venturi of the carburetor.3. Aircraft engines run magnetos because they need no external power to produce spark other than being rotated by the engine a (FAA requirement) 4.Aircraft engines are not torn down every 300Hrs for overhaul. Most Continental and lycoming engines have an overhaul period from 1200 to 2000 Hrs. 5. The statement that 90% of aircraft fly below 5,000’ is incorrect, for example at Denver 100% of the aircraft fly above 5000”, and is true for most of the California if your flying east.
That said, I race a 340 powered Dart that runs 12 seconds. I have run 100LL with a .2 penalty; I did not re tune for the 100LL. I have run 100LL in my ford truck (the mileage is poor), I have run it in my 125Hp. Evinrude with no ill effects, It’s very stable, It will stay fresh for over a year. Try that with pump gas. I hope this will help. Oh BTW, I have been in Aviation for over 30 Years.

www.syix.com/jneal

[url]www.y-sa.com[

[Walkercolt]

Dart66, carburator icing CAN be caused by water in the fuel which why the API and ASAE and FAA require no more than .005% water in Av-gas."Oil and water don't mix" right, that's why every oil lease has seperator tanks. Unleaded gasoline will absorb over 5% water under the right conditions. There is an ASTME test for this. You should contact Aircraft Cylinders Inc. in Tulsa,Ok on the 1200 hr. cylinders...he's making a fortune because no aero mechanic or FAA inspector knows this. His plant is less than a mile from my house and I realise it depends on the application, but the 1949 AirCoupe I took lessons in engine had a 300 Hr. between major inspection rating. A co-worker of my Father's owns an AT-6 Texan. Due to it's age and big Wright radial, that engine has to be re-built(at Air craft Cylinders Inc., he's one of less than a dozen places in the US approved to work on them) every 300 Hrs, or 150 Hrs if you use "War Emergengy" power settings.(Push the throttle thru the"gate") I don't doubt that multi-engine aircraft engines not older than dirt don't have as strict of maintanece requirements, but old engines do.

[66Dart_GT]

Walkerolt

The following link will clear up any confusion on carburetor ice.

http://www.sacskyranch.com/crbice.htm

Second, Of the several The North American AT-6’s I have maintained and flown, all had Pratt & Whitney R1340 9 cylinder radials. I know of one T6 that was modified for air racing that had a Wright to my knowledge it flew only once, The 1340 P&W today serves as one of the major power plants in agricultural aviation. Thy routinely get 800 to 1200 hrs, being you live in Tulsa, go visit Covington aircraft engines, I believe they are the largest over hauler of R1340’S and are very good people.

Third I have not seen “war Emergency” on a T-6. The North American P51’s had a war emergency and they had a gate with safety wire protecting it.

Regards
66Dart_GT


Ops, Covington is in Okmulgee, OK. My mis

[Walkercolt]

66 Dart, Ed Issacsson's "AT-6" is a Navy version, and not an SNJ. I call it an AT because most people don't know the Navy used them too. I really don't recall the Navy designation. His actually has a Wright R-1820 Cyclone 9 cyl. out of a Douglas Dauntless, complete with the three bladed prop and the different gearbox. I do not know the reason for this engine. I have flown in it with him 4 or 5 times. The operating costs are brutle! Put at least 20 gal. of "Gulfpride 80W" in the oil tank, 60 gals 135-150 in each wing tank, and if your careful you burn 25-40 gal per hour.When you "walk the prop" it promptly dumps several gallons of oil on the ground. He hangers it in Tahlequah, OK about 60 mi. SE of Tulsa. It has never been wrecked or had any damage to it. It's heavy ,but quite powerful, but fuel consumption keeps you from going to altitude or pushing the speed.I have always flown with him in the summer.We'd climb just high enough to get cool, and stay around 135 knots IAS, to save fuel. The difference in it and the AirCoupe is about like going from a go-kart to a 440 Max-Wedge Superbird, and then some. The "AT" lands nearly as fast as the 'Coupe can fly.

[dwayne penner]

keith W

your right, the big reason that we use mogas (automtive fuel) in aircraft is price. I have used it myself to 9-10 thousand feet ASL with no problems, however it is more prone to icing the venturies in the carb.

100LL is the most common av gas, and you can tell it by its light blue colour. LL stands for low lead, so this is still a leaded gas. It smells more like premium pump gas unburned, and more like race gas burned.

Another interesting fact, is when you get an STC (suplimental type certificate) to run mogas is an aircraft is usually specifies regular, not premium.

One other rumor that may be related is that most refinerys have a continous run of regular, but do batches of avgas due to lower consumtion. Therfore the avgas may be stored for longer, thus quality is reiant on storage conditions and time.

anyway, more fuel for the fire