Diluting your fuel would be ok, if you have done dyno testing to know
that you are not having detonation and can run lower octanes. Even
with the dyno, that is a test under one set of atmospheric conditions
and it is unlikely that you will have the same at the track. It would
be better to be safe with too much octane and loose a little power,
than to not have enough and loose your engine to detonation. It looks
like my head gasket leak a couple of weeks ago was due to detonation
that blew my copper wire O-ring out of place. I did not get a chance
to try out this new engine configuration on the dyno, so I paid for it
elsewhere. I was using 110 Sunoco leaded.
Also for the few of us racing in SCCA, we can not just use any pump
gas, since oxygenated fuels are not allowed to be used. Around the
northeast non-oxygenated pump gas is hard to find. I have learned
from those that have done dyno comparisons of oxygenated fuel, you
will make more power, but may also have to run richer jetting.
That's my $0.02. Joe(B)
----- Original Message -----
From: <wgrosenbach@juno.com>
To: <fot@autox.team.net>
Sent: Tuesday, May 18, 2004 1:59 PM
Subject: Re: out of fuel- I think?
> When my computer came back from computer hospital it no longer had
the
> info from Union Oil in it, or I would forward it. As I recall, their
110
> product has 4.0 g/Gal of TEL. Most of the leaded race fuels have
near the
> same amounts per gallon. My understanding is that very little TEL
makes a
> fairly significant increase in octane and you can't raise octane
much
> more even with large quantities of TEL. Most of the octane of a
> particular fuel is the result of the refining process and the base
stock.
> At 4.0 g/Gal, there is more lead than needed to achieve the 110
octane
> rating but is there more for its lubricating properties for the
valves in
> the very high pressure environment.
> Have been mixing race fuel 1:1 for years with good results. I was
shocked
> when 1:10 was suggested, but he insisted it would still provide a
high
> enough octane.
> A local engine builder with engine and chassis dyno facilities has
proven
> that any given engine only needs so much octane, and more will
actually
> reduce power output. There seems to be a lot of racers who are
dedicated
> to spending as much as possible for race fuel. There is a CO-OP
north of
> Denver that sells Union Oil 110 for $3.75/Gal at last check and it
is
> even less if you join the CO-OP. Meanwhile, others are paying $4.50
to
> $5.00/Gal from other sources and show no interest in saving money.
> I'm not sure how much premium unleaded fuel octane is increased by
the
> addition of a little TEL, but at 1:1 you would have 2.0 g/Gal which
is
> still more lead as I recall than leaded fuel had at the pump before
it
> was banned. With hard valve seats that should be more than enough.
At
> 1:10 TEL would be 0.36 g/Gal. Not much for lubrication but should
still
> affect octane. Don't think I would dilute that far, but why not save
a
> little to spend on tyres, or something.
>
> Bill
|