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Author Topic:   AV GAS
eric08
Member
posted March 31, 2003 10:20 AM
That's what i plan on running,sometimes it's hard to get they are not allowed to sell it for street use even tho you will be using it for racing off road they will assume otherwise,one trick i've learned is to use someone's tail number and tell them you are getting it for someone working on their plane at home and give them the number you borrowed and you should be ok.Some may say premium unleaded will be enuf but i like the peace of mind av gas gives in case something happens which might send the motor into detonation,also racing fuel seems to keep going up and in my opinion is way overpriced.


Flatlander
Member
posted March 31, 2003 01:04 PM
If you are running flat tops i assume your compression is around 9:1 or 10:1. If so I would think good 92 pump gas should work for you but if you want to mix why not just mix 1/4 race gas(110 octane or so) and 3/4 premium(92) pump gas. On a 20 gallon tank that would give you around 96 which would be more than you ever need. That way all the fuel you put in your tank is formulated to run on the ground not 20,000 feet in the air, and i am sure it is easier to get ahold of.


eric08
Member
posted March 31, 2003 04:25 PM
avgas is junk...

run it one week then run premium and youll see.

youll be changing your jets when you change fuel avgas takes a ton more jet if i can remember correctly, its been 7 years since i was educated on fuels.

avgas is rated at 100 per diff standards than pump gas its the same as premium. call someone who sells ultralights and ask them what to run for fuel. theyll tell you avgas or premium.

rico 08
Member
posted March 31, 2003 09:05 PM
Alot of aviation motors are at least 10-1 compression and are really high output so they need a really good fuel,also they gripe about fuel prices too so they try to keep the prices down unlike racing fuel,if you have any motor at all i'd run the pump gas,the service station premium is no good for racing,saving a few dollars is not worth a racing engine.


dirtbuster
Member
posted April 01, 2003 09:13 AM
I beleive 66jj is right the AV gas octane is rated differently than regular auto gas.

i agree that some airplanes have high compression, high output engines but they also are not flying at sea level. As you get higher the air thins out so it effectively decreases your compression because you cant get as much air in the motor.


Flatlander
Member
posted April 01, 2003 12:04 PM
that's another reason i won't run track fuel is most tracks use the 55 gallon barrels and in the summer/sunshine they have to loosen a bung to keep the barrell from balooning,then if they don't tighten them and they get rain on top when the barrell cools down it will suck in the water and foul up everyone that runs it.


eric08
Member
posted April 01, 2003 01:45 PM
i have run avgas for 2 years and never had a problem, i always add a little 2cycle oil to mine,because avgas is so dry!!!!


eric08
Member
posted April 01, 2003 03:36 PM
It's not that bad,anything is better than premium,i've seen many engines blown on premium.


Earl Parker II
Member
posted April 01, 2003 06:40 PM
You might want to go to http://www.parkercarburetion.com/information.html and scroll down to the 'Racing gasoline vs. aviation gasoline' link- interesting reading.

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Earl Parker II
www.parkercarburetion.com
704.482.7588


racer2
Member
posted April 01, 2003 07:02 PM
ran av gas for 6 years with no problems.
just add oil ,but have run dry before.
and i do run in the front of the pack.


Flatlander
Member
posted April 01, 2003 08:26 PM
Actually, I believe Tim used those figures to illustrate the point that, in general, most racers are better off using fuel designed for racing engines, regardless of the class they're racing in.

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Earl Parker II
www.parkercarburetion.com
704.482.7588


chevy_20
Member
posted April 01, 2003 10:00 PM
I've used av gas for 2 years now. I haven't had a single problem running it. The airport i buy the gas from told me that they test the octane of the gas periodically and the 100 actually was about 115 octane. They told me that it wouldn't hurt my engine to run it as long as i use a top lube like marvels. They also told me to store it in an air tight container because it absorbs moisture more than reg gas.


CAGEMAN
Member
posted April 03, 2003 02:21 AM
I run Avgas, always have always will, I have never added any LUBE to it but I havnt noticed any problems, 54 nights on current motor and she looks good inside.
As for the 20,000 feat thing, airplanes do run on the ground, and also at high altitudes, thats why they adjust the air fuel mixture in the cockpit as they climb. Having to change jets in a race car is an everyday thing, not just because of avgas.
12 to 1 on a two barrel is good for avgas. sure a 10 to 1 motor might run on premium, but the avgas has lead in it and is only a few cents more nowadays.


rico 08
Member
posted April 03, 2003 05:37 PM
You're absolutely right cageman also a 10-1 motor can run on 91 octane i agree but it leaves no margin for error or it will ruin the engine.


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