phase out of 100LL fuel by 2016-17

by **T210DRVR** » Wed Dec 02, 2009 3:38 am

I'm under the impression that most of the Comanche fleet is certified to run on 92 octane fuel. I haven't researched the TCDS of the models, but that is what I'm told. I suppose for us turbo'd models removal of the turbo system might be an option. I think the system on my '64 Turbo Twinco was installed under an STC so removing it should be possible. However, locating all of the original induction plumbing might be hard to find...

by **JIMICS2452** » Wed Dec 02, 2009 1:22 pm

I can not say what is high performance since the term "high performance engine" was left undefined at the panel forum. However, Per the TCD (A/C Specification No, 1A15), the naturally aspriated single engine Comanche PA24, PA-24-250, and PA-24-260 are authorized for 91/96 grade aivation gasoline. The PA-24-400 and the PA-24-260 Turbogharged are required to use 100/130 grade.

So, if I were to use a Broad Brush, I would say that most SE PA24's will run on 94UL. There might be a requirement for modifications to valve guides and valve seats.

Lycoming was very coy about this subject and was conspicous by their absence at the panel discussion.

Jim Hiatt

by **Ben Ayalon** » Sun Dec 06, 2009 11:36 pm