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Spitfire performance, part two

To: spitfires@Autox.Team.Net
Subject: Spitfire performance, part two
From: Mark J Bradakis <mjb@cs.utah.edu>
Date: Wed, 21 Oct 1998 00:14:11 -0600 (MDT)
Our cats are all inside, so I won't be dashing off in the middle of a message
to stop a raucous feline spat outside my office window, as I did last night
while typing away.  If I do ramble on too much, though, I imagine you'll wish
I'd gotten distracted.

Anyway, a couple of comments on horsepower.  Around 1973, Road & Track had an
article on Spit and GT6 performance mods.  With the then recent Spitifre 1500
mill as the subject, Triumph's West Coast competition advisor Jim Coan did some
dyno testing.  With dual SUs, a hot cam, about a 10.5 compression ratio and
some free flowing headers, they got a peak of 95 bhp.  A bit over the 1 bhp/cc
figure mentioned earlier in this discussion.  Hmmm, maybe for next year's
VTR autocross I should build a motor that meets the more liberal VTR rules,
with a cam and a compression ratio similar to this 95 bhp engine, rather than
the current motor in Killer that might make 80 on a good day, but is legal for
the SCCA class in which I run.   Perhaps that's what I need to get FTD away
from a certain pesky red TR4.  Hey, it could happen.

There's more than just the motor involved in having a car that performs well
at full chat.  One factor often underestimated by your typical shade tree crew
is having all the controls work well.  Sloppy, vague steering, mushy or uneven
brakes and loose suspension can all contribute to making a car feel like it is
not performing at its peak.  Hey, no wisecracks about Killer's clutch at VTR,
please!  Putting in some time and effort, as well as a few bucks for parts can
yield lots of rewards in the grin department everytime you drive the car.  As
a side note, speaking of suspension parts, the QSK88 front end kits I
advertised while wearing my Fat Chance Garage hat are gone, I am now out of
stock on that item.  I'll likely get some more in within a month or so.  And
likely will get some more poly bushing sets on hand as well.

So don't worry too much about peak power, torque curves, intake charge velocity
and such until the car is basically sound and solid.  That's my advice for the
night.

mjb.

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