130LL was about 104 Motor octane which I have not seen in years
( It was red if I remember right).
Av-Gas is not rated the same as motor fuel. And it does not have the lighter
hydrocarbons in it. Pump gas is rated by Motor octane plus research octane
divided by two. Av-Gas is blended for higher altitudes and was not rated using
the
M/R 2 scale. Anything in pump gas with a octane over 100 is theoretical kind of
like
a
grade 9 bolt. Pump gas is rated with a blend of two hydrocarbons notane (0) and
isooctane (100). Adding Toluene is a easy way to increase octane in pump gas but
you can not be consistent because the blend of pump gas changes with locations
and
seasons. If you need over 92 octane (over 10.5 compression) I suggest you by
racing
fuel. There have been a lot of engines lost due to some one running Av-Gas or
home
mixing special fuels.
Doug Mallory
Member : SAE
P.S.
Don,
I got to fly a Pits SU-2 last month. Talk about a Tiger with wings.......
Doug
Rich Atherton wrote:
> I never mixed the two, but I used to go up to Paine Field just north of
> seattle with a 55 gallon Drum to get Av-Gas for my dads Sea plane...at least
> that's what I told the guy at the field. I even had a Tail number for him.
> Read it of some sea plane that flew by one day when I got the idea. I used
>the
> Av-Gas in my Bike. It was a Honda 550 Super Sport, that I had completely
> rebuilt into a road race rocket. 651cc kit, Yoshimura road race cam, 13.4 CR,
> and all kinds of other things to sustain the 14,000 RPM red line. It took two
> days of grinder and porting work just to get the cam lobes to clear the heads
> cam galleys..it was a HUGE cam.
> Anyway, this thing would ping and knock like crazy, timed where it was
> supposed to be. rather than reduce the potential perormance and detne the
> beast, I used the Av-Gas to achieve the more than anticipated horse power. It
> had 79hp at the wheel @ 12,300, and dropped to 74hp at 14,000. This was one
> very fast 550. with a 330 lb rider (me), it would pull over 155 on flat
> freeway. This was a 750 - 900cc bike killer. One drum of the Av-gas would
>last
> about one season of riding. God it was fun...But the constant tuning required
> to keep it there became a real drag. Weekly Valve adjustments, and dealing
>with
> all of the problems associated with a bike desinged for half of that power. I
> just got tired of changing parts. I had more 750 parts than 550 by the time I
> sold. I miss the performance. had fore-arms like Popeye back then from
> holding on to that thing..
>
> AvGas is great !! I highly recommend it......
>
> Rich
>
> >This is a trick that we in aviation have used for many years (for our hi
> >performance cars).
> >
> >When 100/130 octane was available, you could mix as little as 5% and
> >apparently raise the octane rating (knock resistance) significantly.
> >
> >Best regards,
> >
> >Don Cordier
> >Aviation Consultant
> >Glendale, California, USA
> >doncordier@earthlink.net
> >
> >Office & Hangar: (818) 997-7640 (24 hours)
> > FAX: (818) 553-3667
> >Member: NBAA, NATA, PHPA, AOPA
>
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