A gasoline engineer once explained to me that higher octane is slower
burning (to prevent pre-detonation in hi compression applications).
This results in less specific chemical energy output.
In a hi compression engine this is a minor loss compared to the overall
gains from higher compression. In a standard engine this remains a minor
loss in horsepower, period. Although it doesn't hurt the low octane engine,
it unnecessarily dings the pocket book.
I forgot to ask him if there are other additives, that perhaps add to the
story that you should run hi octane before an emissions test.
Mike
60 MGA, 67 etype, 59 Bugeye
Toronto
----- Original Message -----
From: "Paul Hunt" <paul.hunt1@blueyonder.co.uk>
To: "Charles & Peggy Robinson" <ccrobins@ktc.com>
Cc: "MG List" <mgs@autox.team.net>
Sent: Tuesday, August 29, 2006 7:59 AM
Subject: Re: Shell V-Power
> Not so, of the octane ratings we are talking about the higher ones
> definitely give better performance, economy, and lower running temps on a
> standard engine. I know, I've experienced the results when having to
retard
> the ignition to cope with the lower grade. Of course, if your engine has
> only ever been tuned to run on the lower grade then you won't know what
you
> are missing.
>
> PaulH.
>
> ----- Original Message -----
>
> > Of cuss, you don't need all that octane unless you're running a
> > much-modified engine.
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