[Cobra #3170]

Originally Posted by David Kirkham

3170,

Yes, the suspension has been on my mind for quite some time now. Thomas and I are really working hard on trying to figure out how to decouple roll, pitch, heave, and warp--as you know, this is a bedeviling problem. There are no free lunches and controlling one inevitably "controls" another one (in a way, it always seems, that you don't want)! For the track, it seems Chapman's saying, "Any suspension will work--if you don't let it!" is the cure for Cobra ills. 1000 pound springs work well on a smooth track, but not on our customers' bums as they drive down the street

Our conversations in the past on suspension have always stuck with me. (I always remember what you said about hitting pot holes with the brakes on and watching the loads skyrocket.) There is an answer to this problem--we just need to find it.

David

Well said David,

It all starts with the chassis and I'll bet your beautiful new coupe goes a long way towards resolving that issue. A stiff chassis can tolerate high loads without all the ill effects associated with a lesser chassis with the same high rate springs. I have a 2005 Ford GT that has a rear motion ratio in the high 9's and a front motion ratio in the high 8's, I run 500 lb/" front and 800 lb/" rear springs and the ride is quite tolerable considering the super high wheel rates. The secret is the chassis is over 20,000 lbs/D. in Torsion. A wimpy chassis will actually give diminishing returns if the springs and bars cause the chassis to displace under load, so Chapman's theory only works to a point.