ok, over the weekend, something changed my mind...

whats the ideal spring rate for Front and Rear?(Roadrace oriented)

for instance, tein springs some as 6/10 kg, and 8/12 kg(thats front/rear). stiffer springs out back provide for what? same Q for the front. sorry, but i think i lost some brain cells over the weekend.

 

anyone know the spring rates on coilover kits such as Skunk2 or GC, are the spring rates in front higher than the rear?

 

Stiffer rear springs provide a looser, more tail-happy handling attitude while stiffer fronts bias the car towards understeer (which can be balanced by a stiffer rear sway bar). Skunks I believe are 400f/500r and the standard GC kit is around (depending on the car) 325f/275r. My opinion is that you want a more neutral or understeering car for the street. If you have a racecar, def. go stiffer rears, but otherwise you can get yourself in trouble on the street when you're just trying to have a little fun. You probably want to build some understeer into the car if you aren't an experienced racer (and you don't sound like you are, no offense. I'm not either). Skunks are VERY stiff for a street car. My advice is to decide what you want for your car. Make it a street car, and you can get softer springs and a better ride with better handling than stock, or make a racecar and go very stiff with a loose rear end. If you really are going to seriously roadrace it (competetively), front springs should probably be in the 500-700 range, and rears in the 700-900 range with revavled Konis. That will however be totally unstreetable. Depends on what you want. My .02.


[Modified by tylerdurden, 5:57 AM 10/28/2002]

 

tylerdurden- Agreed, with some added input.

Running very stiff springs in the rear will get the tail to rotate easily, but also make it easily upset and get the whole car feeling twitchy. The problem is that any bump encountered gets the rear very unsettled, and as a result heavy braking into anything but a super smooth corner will have the car wandering all over the place. For this reason alone it's better to tune the suspension's balance with sway bar stiffness and only use the f/r spring bias in a small supporting effort.

Besides that, my only input is that there's no single correct spring stiffness for any car. What works best depends upon the driver, the track, and the conditions. Any of these three variables can change the optimal suspension setup significantly, so the only correct answer for suspension setup becomes "whatever works". One track might have plenty of long sweepers that require prolonged throttle on exits, which would favor stiff rear roll control to keep the car from understeering too heavily. Another may be full of tight kinks, where a driver adept in trail braking might be better off with a softer rear setup that lets him dial in chassis rotation by attacking corners with the brakes. These are just two examples among many, illustrating the point about different drivers/tracks/conditions dictating which suspension setup works best on a given car. Hope this helps, peace.


[Modified by texan, 12:20 AM 10/28/2002]