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Modestly Technical Unleaded Avgas Presentation

very good review

This is a very good review of avgas. It also talks about Mogas and the ethanol mandate. Lots of stuff in here on the technical side of gasoline production. Very well worth the few minutes.
 
On the transmix issue: seems like the stuff would be perfect for those of us who happily burn suitable mogas in our Lycomings.

Don't truck it back cross country to the originating refinery for reprocessing; sell it as "discount tank-car gas" to guys like me who burn 91/95 mogas all the time and 100LL when that's what's available on the road. I'm sure my engine and I don't care what the exact composition is as long as it's gasoline of known pedigree and vapor pressure and has no ethanol in it.
 
What was old is new again.

Very interesting discussion - -fuel blend from 1943 - fighter fuel - - that should calm the turbo/supercharged crowd nicely.

Do the Reno guys use this fuel in the racers? It certainly sounds like Braly could not get it to detonate with much higher boost even with extreme temps as required in the FAA test. Maybe this opens the door for more efficient turbocharged/aftercooled with moderate boost and lower displacement. That is what the diesel industry did (still doing) for 50 yrs.

Hmmm Xylene - makes a good parts cleaner!!

One thing - he stated that this is the same formulation as they presented to FAA in 1994 (?) but there was a reason FAA would not approve for the industry. I did not quite understand the implications of that statement and how it would affect us. Can anyone provide some illlumination?
 
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Very interesting discussion - -fuel blend from 1943 - fighter fuel - - that should calm the turbo/supercharged crowd nicely.

Do the Reno guys use this fuel in the racers?

Many Reno guys are using auto race gas like VP, usually with high aromatics plus more lead than 100LL. https://vpracingfuels.com/product-category/racing/racing-fuels/

Some of these blends are oxygenated as well.

Lots of folks seem to be concerned about the knock resistance of the GAMI fuel for their "high" compression Lyconentals. It's already passed extensive testing on turbocharged engines. No way the FAA would approve it otherwise.
 
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I was really pleased to hear that the new avgas formulation meshes in synch commercially with the seasonal car gas blending! After hearing the details (as released) on the product and its formulation, logistics of distribution, etc., mixed with a little refining experience few decades back, I'm actually optimistic about the new product.
 
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.....One thing - he stated that this is the same formulation as they presented to FAA in 1994 (?) but there was a reason FAA would not approve for the industry. I did not quite understand the implications of that statement and how it would affect us. Can anyone provide some illlumination?

@Bill. Best guess is as follows:

It was mentioned by GAMI that the 100LL spec was written around the formulation/properties of the existing product; not vice versa. If true, the only easy chance of meeting every part of the spec is with 100LL (minus the TEL, of course). It has been mentioned in several threads here that it was this mindset (meet or exceed every aspect of the existing spec < TEL) that doomed any economical successful result from the PAFI efforts. Very easy to see that every box isn't checked even if it's not pertinent to the product's overall success.

This ignores the other below the table, ulterior motivations already mentioned; big oil influence/profit-driven/FAA ineptitude/regulatory capture/etc. but as mentioned it's my best guess based on the latest releases. This movie is far from over.
 
https://youtu.be/6h9gYND3xFo?t=104

1:44 into the Paul Milner interview, Xylenes in G100UL vs. Tolulene of Avgas.

I think that answers Bill's question best. Watch to 3:50 in for the octane enhancer, which shows up in the patent.

The FAA wanted, for years, No Lead Avgas that looked just like TEL/100LL without the lead, which did not catch on as it would not support all existing engines.

https://pubchem.ncbi.nlm.nih.gov/patent/US-2014128644-A1

"Selected aromatic amines, such as m-toluidine, may also be added to increase motor octane number"
 
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https://youtu.be/6h9gYND3xFo?t=104

1:44 into the Paul Milner interview, Xylenes in G100UL vs. Tolulene of Avgas.

I think that answers Bill's question best.

What also was interesting is that he mentioned that xylene is in excess in the summer months (they need to refine it out of auto gas for the summer blend), which means it is cheap then. Will be interesting to see if that helps to keep the cost delta down.

Larry
 
https://youtu.be/6h9gYND3xFo?t=104

1:44 into the Paul Milner interview, Xylenes in G100UL vs. Tolulene of Avgas.

I think that answers Bill's question best. Watch to 3:50 in for the octane enhancer, which shows up in the patent.

The FAA wanted, for years, No Lead Avgas that looked just like TEL/100LL without the lead, which did not catch on as it would not support all existing engines.

https://pubchem.ncbi.nlm.nih.gov/patent/US-2014128644-A1

"Selected aromatic amines, such as m-toluidine, may also be added to increase motor octane number"

Post was significantly edited from first go.

Sticking by my original point. The spec was written around the 100LL product. It is a performance spec; not formulation based. The only constituents I remember it specifying was sulphur, probably for emission requirements (odorants) though it would contribute to hot corrosion.

Lots of potential products would have worked but workable issues like density or even (too great) a heating value "disqualified" them. Would anyone really care about which aromatics are used if it works?
 
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