Re: using a pyrometer

[Simon Favre <simon@domain.elided>]

The usual procedure seen at local tracks goes like this. The driver goes
out for a few hot laps, then comes into the hot pits for a tire check. A
properly attired assistant jumps out almost before the car stops, and
takes 3 readings off each tire as quickly as possible so the tires don't
have time to cool. You want readings from the center, inside and outside
of the tire tread. Slightly higher in the center is OK, but too much
higher in the center indicates too much tire pressure. Higher on the
outside indicates too much body roll, or not enough negative camber.
Higher on the inner edge indicates too much negative camber. The other
thing I would try to use setting up a 105 Alfa for racing is a camcorder.
Not one inside the car, that's for driver feedback. What you need is to
have somebody trackside get video of the front of the car, head-on as
you go thru a tight corner. This will tell you in a flash if you are
rolling the tread over, or leaning the car so badly you get positive
camber on the front tires (a *bad* thing). Chalking the tires all the
way across at one point is helpful. 

The problem with adjusting corner weights on a production car is that
it's a royal PITA to adjust the springs with spacers. If you do it, you
should do it with the car as raced, ready to go, with driver in place.
I use a set of Rugglescales on my Formula car, but with a coil-over
suspension, the adjustments are pretty easy.

A full dissertation on suspension dynamics is beyond both my abilities
and the scope of this digest. There are numerous books, tho. "How to
Make Your Car Handle" by Fred Puhn is considered a good primer.

Simon

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End of alfa-digest V7 #1025
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