Av gas

[Doug Bazarnic]

I use nothing but AVGAS 100LL fuel in my '85 Corvette and on occasion in my
supercharged truck for towing in the summer.   Think of it as Turbo Blue,
but much cheaper! ($1.56 a gallon)

When running it in your computer controller car, make sure you use a lead
tolerant O2 sensor.  Otherwise a brand new non-lead tolerant 02 sesonr will
die in just under 1 tank of gas.  (I went thru a few of them before my lead
tollerant o2 sensor arrived)    I run AVGAS in the Vette because of my high
12.4 compression.   Mix that with 110+ degree days, and NO pump gas will work.

Planes use AVGAS for another reason -- because they are often at 100% power
more often and for longer durations than any street car engine.    How
often do you cruise at 75% throttle on the street? :)     

One other point...   AVGAS octane rating is derived differently than pump
gas.    It's octane numbers are derived from the J3 + J4 / 2 method,
whereas pump gas is Research + Motor / 2.  I haven't found any source that
explains what the j3 and j4 method are and how they compare to the R+M/2
method.

Point number two:  There are no plans to get rid of leaded fuel for
airplanes.   Planes made to this day require leaded fuel for valve sealing
and anti-detonation properties.   Unlike cars,  planes tend to stay in
service for many many decades.

People that have problems running AVGAS in vehicles must take note that it
is less dense and fuel mixture curves must be adjusted.  Those with 02
sensors need not worry. :)   AVGAS also does not idle well when it's cold
out.   You'd be surprised how light a 5 gallon can is.

The downside to AVGAS is the stink!  :)

Doug Bazarnic

http://www.primenet.com/~dougb/vette.html  
85  Vette 383 Auto 3.73 gears
407.6 HP & 397.7 ft/lbs @ rear wheels on AVGAS
11.887 @ 119.24 mph