>snip<
   Even worse, according to our local Chrysler Service Manager.  He told me
a couple of years back that the major complaint he had was driveability, and
the major cause of driveability problems was people running hi-test in
lo-octane cars.  Something about the ingredients/additives in the
hi-octane??  The customers often initially fought his analysis, but tried it
since he gave it to them in writing.  Many came back or called and thanked
him.
   Don, below, did a seemingly good test, but he admits it was not
conclusive.  I noticed that some older Buick Ultras with
Superchargers--check & lemme know if I'm wrong--had lower compression ratio
than the non-s/chg'd., something like 8:1 on the s/chg'd. and 8.5:1 on the
non-s/chg'd.  On the surface, lo-octane seems ok.  Actually, I've known a
few customers who used it exclusively after even shorter tests than Don, and
claimed NO diff. in mileage.  These were VERY conservative drivers, who may
get by as such.  But I, who am a conservative for 98% of the time, like to
"feel" the power once in a while: this makes up the other 2%.  I'd think the
s/chg'd eng. would HURT during this 2%.  And who knows when I'll wish to
"feel" it?  Needs hi-octane then!  However the knock sensor detects my foot,
lowers the timing via computer, runs inefficiently thru this otherwise
hurting time, and fails to let me feel what it really had, being constrained
by all the lower parameters than ideal!
   So, for the average driver who uses his passing gear infrequently, what
does he do?  He's better off, IMO, to run the hi-octane always.  This way,
the car's 'muscles are not strained to the point of serious damage' when it
infrequently climbs a hill with an arm tied to a foot = while in passing
gear, when the s/charger blows hard and knock sensor retards timing to its
max (or min!)--a condition not recommended by either Buick's mfg. OR us
builders of more conventional, hi-output engines.
   So, who could benefit from using the lo-octane in this car?  My dad was
one--notice I said WAS, as he's no longer down here with us.  I'm sure I had
a couple of customers who could also benefit.  But after this counting,  I
still have a couple of fingers on one hand not being used!
   My opinion, ONLY.
sam