I have just learned of the effort to eliminate 100 LL fuel. I have an 0-235 engine with the Sparrow Hawk conversion and am required to burn 100 LL not MO gas like other 0-235 stock engines. The Sparrow Hawk has higher compression than the stock 0-235.  Does anyone have any details if the replacement fuels will be compatible with the higher compression engines? I know when 80 octane leaded fuel was phased out I had all kinds of cylinder problems with my GO 300 engine and would hate to go through that again


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Yes!  That is why it is taking years to find that critter.

Not sure if this fuel will fit the bill, but they had a display at the Light Sport Expo this week. They are up and running and trying to expand their distribution.


I see they have 94  & 102 octane, but my FBO only has one tank and pump, 100 LL. Always something to worry about 

Swift will also install portable tanks and pumps.

Swift has been testing UL 94; don't know if that will meet your needs. Shell is also testing, but I'm unsure what octane rating they claim.

Gil, It is my understanding that by definition, the approved replacement for 100LL will be acceptable for any engine that currently runs 100LL.  Otherwise it would not be a true replacement.  100LL itself was a compromise as it replaced three grades I know of and there may have been more.  Seems I remember 80, 100, 145 but I don't rely a whole lot on my memory.  :-)

I read from the Swift information page, but I didn't quite understand all of it. Like you, I would think a 100 LL replacement would cover all engines now using it, but then why have two different grades to replace 100 octane LL? I will call Swift and ask.

I did not mean to imply that a single fuel must be used.  But I don't really note exact spec they are working toward.   I guess ideally there would be as many grades as there once was, as engines were designed and manufactured for a specific octane and lead contend.  The 100LL was a compromise.  Both octane and lead content above the old 80 grade and much less than the 145 grade.


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