Re: 88, 89 imsa cars

[Eliot Lim <eliot@u.washington.edu>]

On Sat, 16 Dec 1995, Daniel Hussey wrote:

> I'm sure y'all know more about this stuff than I do, but I seem to re
> member a 200TQ (Group 44) IMSA race car.  
>I believed it raced in the IMSA GTO series

yes, they did race in IMSA GTO in 1989, but the car was not really a
200TQ or even something made to resemble it.  it was a purpose built
pure tube frame race car with kevlar panels formed to *resemble* a
90Q.  it was officially called a 90Q, but the only things it had in
common with a production 90Q was the 4wd and having 5 cylinders.

for example, it had double wishbone suspension and carbon fiber brakes
while the trans am car had steel brakes and struts.

> Anyways...I thought there was a 200TQ race car
> too.

yes, that 200TQ raced in 1988 in trans am, while the "90Q" raced in GTO
in 1989. the cars had an identical color scheme and a 3 box shape.  that
would probably explain your confusion.

the jay lamm book "all wheel drive high performance handbook" has a wealth
of information on both the 1988 and 1989 audi racers.  lots of photographs
too.

i also found this passage of another quote of race engineer brian berthold
regarding the 5000/200TQ trans am racer of 1988:

[all the capitalization is mine]

"in trans am racing you're allowed to push the engine way back, but because
of the fact that we used the STOCK ENGINE AND GEARBOX, and you need the
axles to come out along the front wheel centerline, we couldn't do that."

1) eric, where did your information about using an aluminum block come from?
"stock engine" to me would mean iron block.

2) THEY USED A STOCK GEARBOX!!!!!!  the turbo engine was putting out about
500 bhp, according to lamm.

more details on the trans am car: (sorry, dan, i will post details on the
GTO car at a later time.  i am more fascinated with the trans am car)

"as is standard practice, the roll cage was designed not only with driver
safety in mind but also to stiffen up the UNIBODY and achieve some of the
rigidity inherent in a tube frame.  not only were tubes added to completely
protect the driver, but they were also run forward through the FIREWALL
to brace the shock towers holding the PRODUCTION style macpherson struts."

"audi's tight production schedule demanded that a tremendous number of
production pieces be used inside the stock UNIBODY, though the rules
did not.  the gearbox casing, rear differentials, front and rear glass,
much of the rear suspension and many other parts were straight off the
production line.  ``the original prototype for the trans am car still
had opening doors and windows'', berthold recalls.  ``naturally we did
away with those for the actual race car, but [the race cars] were that
close [to stock]''."

"..while the macpherson front suspension was unusual in a series that
allows formula car suspensions, the struts were used because they were
proven pieces that could easily be adapted to the production UNIBODY.
wishbone suspensions would have meant building new pickup points to 
carry them on."

- it is clear (assuming what jay lamm wrote is accurate) that the
trans am car did not lose its hood section monocoque as was suggested
in earlier posts.  the roll cage was extended to the front section to
reinforce it, not REPLACE it.

- further evidence comes from the fact that they had to use struts
up front.  if the front was replaced with tube frame there would
have been no reason to use struts.

any more itchy fingers on the buzzer????  :)


eliot