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Old 01-16-2006, 10:49 AM
slowturbo slowturbo is offline
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Quote:
Originally Posted by xntrik
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If you ever have the opportunity to see pictures of a Fox or SN-95 Mustang doing a maximum effort stop (in lots of magazines) and then the new BMW video ad showing the Beemer stopping..... you will see that the Mustang pitches nose down 3-4 inches and the rear rises 3-4 inches and the Beemer stays almost level to maybe an inch.

Front and rear geometry are fixed by design, and by nature are a compromise of the lift and dive (squat) by their design. What works very well for drag launches is poor for stopping ability, etc.

When a front end nose dives the weight of the vehicle is being removed from the wheels on each end. Actually if the front end did not dive, the center of gravity would stay higher and there would be more downforce on the front tires. If during a stop the front springs were suddenly solid... there would be more downforce on the tires.
I find this quote misleading. It would seem that you are saying that weight transfer under braking is caused by chassis dive, which is incorrect. At the point that the chassis begins to pitch forward, weight transfer has/is already taking place. The only portion of weight transfer that can be assigned to chassis movement would be that caused by the vertical movement of the center of gravity (CG) under dive (or squat under acceleration). IIRC, in his book Tune To Win, Carroll Smith attributes something like 5% of weight transfer to movement of the CG. Additionally, from the formula HERE , weight transfer is purely a function of vehicle weight, CG height, wheelbase, and brake pad coefficient of friction.

Ramblin65,

There are several people on another board I frequent (Moparts), including a couple of autocrossers, who have used and recommend the Praise Dyno brake shoes. You might do a search over there for more info.
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