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What makes a good race car?
Northy - 5/5/04 at 06:20 PM

Didn't think this fitted in any other sections so stuck it in here.

I'm not refering to Locosts here really, just any sort of racing car.

Whats most important for good handling? Low CofG? Low unsprung weight? etc etc....
Can the CofG ever be too low? Is mechanical grip (from the tires) generated by weight transfer?

Cheers


I love speed :-P - 5/5/04 at 07:22 PM

try this site

http://www.kent.k12.wa.us/staff/trobinso/physicspages/po2001/Handling/home.html

go down to the bottom, and then the links to the left


britishtrident - 5/5/04 at 07:49 PM

First leason confuse grip and handling they are different, I have driven loads of cars that had one but not the other.

The key to grip is the friction coefficent characteristic of the tyres, it is always non linear falling off at higher tyre loadings.
For this reason a car with 4 tyres all the same size has maximum theorhetical sideways grip with 50/50 weight distribution fore and aft and right to left.
This is also the reason why fitting wider wheels and tyres give more lateral grip in the dry, of course it is more complex than that especially with racing tyres where tyre temperature is more vital than anything else - too wide a tyre will not generate enough heat to get the rubber working.

When cornering weight transfer loads the outside tyres and a unloads the inside however the additional grip gained on the outside wheels is less than the grip gained by the inside wheels. This is the basis of tuning the understeer-oversteer characteristic of a car by changing the roll stiffness or roll centre height of the suspension at one end of the car.

To get a good background I can recommend the book "How to Make Your Car Handle" by Fred Phun


Hugh Paterson - 6/5/04 at 08:43 AM

Easy the NUT behind the steering wheel
Shug.