Av Gas with a 4-stroke turbo/SC?

[Turbo Tim]

Re: AV Gas tough to Beat

100LL is a highly regulated fuel obviously.. FAA. Technically it cannot even be sold to the public, but it is still available at many mom and pop airports. LL means low lead, it rates very close to unleaded fuels, and many would argue that lead is in fact good for combustion. Its the only fuel you can buy across the globe and know you are getting the exact same product every time. 100LL is often marketed as 104 Race GAS. It has a high MON rating which is high temp heavy load testing (108 - 110) MON factor, which is most important for a turbo motor. (Airplanes are turbos too) The RON factor is 100 - 104. The average of the two, RON+MON/2 is pump octane 104, averaging down. Pump octane numbers are not good indicators of what fuel your engine requires. 100LL is cheaper and better in most cases. Does this mean that VP -12 is not a great fuel for your turbo? NO not at all. But bang for the buck 100LL is as good as it gets. I run it in 15:1 2-strokes with no detonation problems. Also run it my turbo at 15# boost, stock pistons. There are many other factors in fuel such as specific gravity, etc. (A Graham Bell overviews much of this in the two stroke tuners handbook) Well known watercrafter George Grabowski has also published a few related articles. They do not neccesarily recommend AVGas, but if you read between the lines, it's tough to beat.

.........Yeah that too

 

[snowfix]

Re: AV Gas tough to Beat

100LL is a highly regulated fuel obviously.. FAA. Technically it cannot even be sold to the public, but it is still available at many mom and pop airports. LL means low lead, it rates very close to unleaded fuels, and many would argue that lead is in fact good for combustion. Its the only fuel you can buy across the globe and know you are getting the exact same product every time. 100LL is often marketed as 104 Race GAS. It has a high MON rating which is high temp heavy load testing (108 - 110) MON factor, which is most important for a turbo motor. (Airplanes are turbos too) The RON factor is 100 - 104. The average of the two, RON+MON/2 is pump octane 104, averaging down. Pump octane numbers are not good indicators of what fuel your engine requires. 100LL is cheaper and better in most cases. Does this mean that VP -12 is not a great fuel for your turbo? NO not at all. But bang for the buck 100LL is as good as it gets. I run it in 15:1 2-strokes with no detonation problems. Also run it my turbo at 15# boost, stock pistons. There are many other factors in fuel such as specific gravity, etc. (A Graham Bell overviews much of this in the two stroke tuners handbook) Well known watercrafter George Grabowski has also published a few related articles. They do not neccesarily recommend AVGas, but if you read between the lines, it's tough to beat.

.........Yeah that too

We it works well in the carbed versions. Do you think it will apply to the fuel injected as well?

 

[cobaltpilot]

So... is anyone running 100% 100LL Avgas in an MPI Supercharger application?

 

[ken_climb]

Wow this thread goes back away's! wow! Brian, I'm sure you can run 100% av gas with the s/c...,, what do you have up your sleeve now?

 

[cobaltpilot]

I didn't want to start a whole new AVGAS thread since it's been beat to death, but I am curious if I can get away with stage 2 on a Nytro without getting into the head.

Was thinking a good flat-light sled would be this Nytro MTX with the track turned around and a stage 2 MPI SC.

Then again we all know how that simple thought ends up $35,000 later...

 

[BlgsRX-1mtn]

So... is anyone running 100% 100LL Avgas in an MPI Supercharger application?

Yup, I blend the stuff; so I definately know what I'm getting. This video was while running 100LL Av-Gas and 91 octane at a 50/50 mix. http://media.putfile.com/BlgsRX-1mtn-w-boost
The pullies were in the 5 lbs boost config with the primary allready loaded up for 10lbs boost (at this point I was still dialing in the jetting).

I will usually run VP race fuel in a 50/50 mix though when I have to leave the tow rig and trailer in remote areas and ride in since it is available @ the Yammi dealer in Cooke City. It's alot easier than riding 10 miles one way to fuel up then another 10 miles back. I still carry 20 gals of 100 LL just in case the Yammi dealer is out.


Jim