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Yet Another Track Day Report

Delete now if you don't want to read this stuff. In the continuing saga
of PeeKay the Wonder Car and given the theorem that if you aren't
actually driving on the track reading about it is the next best thing, I
thought I'd file this:

Got PeeKay out on SIR yesterday for an absolutely perfect day. Weather
was partly cloudy and 75 degrees. Track was virtually empty. No trace of
the four quarts of oil some hapless novice had dumped on the chicane
during the conference race the day before when his oil pan went south
("I knew you shoulda put all them little bolts back in, Dwayne...").

In Our Last Episode we had loosened the swaybar endlink mounting bolts
(if I were writing about computers I'd immediately dub them SEMBs) so
the rear swaybar wouldn't be binding against the endlinks. Seemed to
soften the rear dramatically. (BTW I'm still waiting for Korman to send
the hardware they were supposed to include with the bars and promised me
over two weeks ago. As always, I'll report my experiences--good or bad.
You make the call.)

However, subsequent track experiences made me think the car had too much
push. So before this event I dropped the front swaybar from full hard to
full soft. Now both bars were full soft. I was nervous the car would be
too loose and dragged along the tools necessary to make an on-track
change.

However, they were unnecessary, which is good, since I remembered the
jack but not the handle... The car felt really good. I was able to
rotate it pretty consistently into a couple of hairpins we have that are
just real tough on M3s. A couple of times the rear end got out on me but
never caused me any problems. By the end of the day we had cut several
seconds off our previous fastest lap times. We got clocked at 1:42 on
one timed lap. A very experienced friend in a RX-7 TT with Konis and R1s
runs 1:39s and this is a horsepower track so the time looked really good
to me. 

However, it's not good enough and we're still doing this setup ass
backwards. You're _supposed_ to get the car balanced before adjusting
swaybars. The car still isn't corner weighted and I'm suspicious that
the spring rates are too stiff. As a result we're losing tire
compliance. So the next step is to get the corner weights balanced and
then try some more. Also if I can get some softer springs I"ll slap them
on and see what happens. Right now the tire temps say too much negative
camber, which isn't right because it's only about 2.5 degrees. So
probably what that really means is that the suspension doesn't have
enough travel because the springs are too stiff.

One side note. I read somewhere that Fangio kept a constant mental
picture of how much each tire weighed as he drove. At least I'm pretty
sure it was Fangio. I kinda got that image stuck in my mind and I've
been trying to do it. It's pretty hard but interesting. It makes me a
lot more sensitive to weight transfer and balance and I think that
helps. I'd be interested if anyone else does this or if they try it what
they think of it.

Cheers,

John Browne
BMW ACA Puget Sound Chapter
BMW CCA
95 ///M3 LTW (PeeKay)
95 ///M3 (gone, alas!)
91 iX (Spunky the Brave Little Car)
96 Suburban 2500 (Godzilla; thanks for the name suggestions!)