Okay.... I tried to stay outta this one... but here goes...
Vp C 16 is fine for a HIGH compression engine... I think the C12 would be
fine for a 13-1 motor... If you go much above that the 118 octane of the C
16 might be a better call... and you might even want to try a jug of it on
your 13.1 motor with a bit more advance...
Octane is just one of the factors we look at with a Race motor.... we also
have to consider specific gravity and the actual research octane Vs Motor
octane....
Here is the deal.... the higher the octane the slower it burns.... the
slower it burns the more timing you can put in the car before you get into
detonation and the less propensity for preignition. Sounds like a winner
eh.... just go out and buy 118 octane and run it eh?.... somehow it just
doesn't work that way.... it's all about where the motor is designed to fire
the fuel and they type of fuel the engine is built around.... our
Compression and Cams in the early Healey's like my Hundred are really
designed around 100 octane fuel which was commonly avalible in the 50's.....
Even Geoff Healey had mentioned that some Pump gas in the US wasn't worth a
damn.... Keep in mind this was when you could actually buy Gas at the
pump.... with today's junk fuel.... there just isn't anything avalible to
run in the Healey without backing off the timing a ton.... So I run one
gallon of C12 with 10 gallons of Premium unleaded.... the C12 is a LEADED
fuel....BUT I only do that in the HUNDRED... NOT THE SPRITES.... ( well Miss
Kathy's bugeye with the 10-1 1275 and a kent cam gets the same treatment as
the 100 )
Any way Fuel is a very complicated issue in a stock sprite.... Pump gas is
just fine.... PREMIUM is always going to be my choice... but that is because
I like to run more timing... Advanced .... you can get away with the
cheapest gas you can find too..... ( ask my son.... it's all he runs...)
Okay enough Rambling...
Keith Turk ( http://downtown.ala.net/~kturk and this month's issue of Chevy
High Performance Pages 124-126 )
----- Original Message -----
From "Rick Snover" <rsnover at ix.netcom.com>
To: "Jacques Le Clainche" <jleclainche@home.com>
Cc: <spridgets@autox.team.net>
Sent: Saturday, April 21, 2001 4:16 PM
Subject: RE: racing fuel
> At 01:08 PM 4/21/01 -0700, Jacques Le Clainche wrote:
> >The compression ratio is 13:1. That's why my engine needs high octane
fuel.
> >As Ron says though, this engine may very well not need as high as 115
octane
> >fuel.
> >
> >I have just bought five gallons of VP C12 (108 octane) to try- the local
> >shop charged me $5.75 per gallon. I can buy the Turbo Blue fuel at $4.95
a
> >gallon- that's what is in the Sprite now...
>
> I usually burn whatever 108 or 110 octane I can find, with no problems.
> Lately it's been mostly VP, but last time I bought some F&L from Race
Ready
> Products down in Chula Vista, for more than $1 less per gallon than they
> were charging for the VP. It worked just fine.
> --
> Rick Snover
> '59 Speedwell Sprite (VARA FP #17)
///
/// (If they are dupes, this trailer may also catch them.)
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