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Re: Octane myth

-- [ From: human * EMC.Ver #2.5.02 ] --

>I don't understand those that proclaim that octane makes little difference.
 The jeep knows the >difference between 87 and 91..  We even found some 94
octane, that jeep just really ran well.  >Maybe the intelligence of Audi
engines make up for some of the octane differences, but to me >"cheap" gas
can mean poorer performance or harm to the engine and the ripoff extra price
still is >inexpensive insurance/maintenance.  <randomly snipped>

>Alan Callery 

The point is not that it makes no difference!!!  "Smart" engines like your
Jeep, obviously, and most of our Audis, are not only designed to take
advantage of higher octane fuels but can retard their timing to run fine on
lower octane.  "fine" is relative here.  You get less power!  I don't think
there's much of a logical connection between "less power" and higher
maintenance costs.  Not with a "smart" car.  Now my 82 coupe isn't smart. 
If I advance the timing (what do you mean "if"?) I'd better run high octane
gas because if I put 89 in it, it will knock.  So maybe I would destroy the
engine.  But that would be my error in tweaking the engine to run only on
high octane, and then running low octane.  

The "smart" engine has  a knock sensor which lets the engine run at a lower
performance level on lower octane fuel - precisely so it won't harm the

mumble mumble.

Huw Powell

Under the wrench:
82ish Coupe (glub glub)
73 F250 "rust never sleeps"

Outstanding in their field:
80 5k, 81 5kt, 87 5ks (royal blood)

so what am I driving? ugh.

HUMAN Speakers
7 Kelsey Road
Lee NH 03824