Stronger Suspension?, Suspension Options

[Dion]

I had a question on the pics forum and was guided to post a new thread. This was probably discussed before, but here goes... I have recently added new steel flares and larger rims(17x7and 8) Does any one believe because of this the susp. should be "BEEFED" up. I currenly have stock BOGE struts and 170# springs.The rims are secured to the original 4 bolt hubs. (IMG:http://www.914world.com/bbs2/html/emoticons/huh.gif) Cheers,Dion

[Dave_Darling]

Oh, I like that "oversteer" pic!! (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif)

Dion, one key point is that suspension setup is all about balance. You have stiffened up the rear suspension of the car very significantly (almost three times as stiff as stock!), and left the front alone. This means that the rear end is very likely to be the one that breaks traction first. (See Rich's picture of the results of "oversteer".) You ought to stiffen up the front suspension somehow to get the car back into balance again.

You can do this by upgrading the torsion bars to larger, stiffer parts. (If my math is correct 23mm might be a decent match?) You can also do this by installing a front sway bar, or increasing the size of the one that is in there. Increasing the size of the front torsion bars is, effectively, increasing the front spring rate, which will make the car's ride significantly harder. Increasing the front sway bar size will not affect the ride quality as much, but both wheels will react when one wheel goes over a bump.

Or you can increase both the torsion bar size and the sway bar size.

The biggest benefit from using a sway bar to do at least some of this "making the front suspension stiffer" work is, as Brad said, because it is pretty easy to adjust the effective stiffness of a sway bar. Not so easy for a spring or a torsion bar...

I, personally, would think about downgrading the rear springs quite a bit. The 100 lb/in rate seems to be a good match for the factory front sway bar (no adjustment though) or the 19mm aftermarket adjustable bar. For 140-ish lb/in rear springs, the 19mm is a bit on the small size but is still useable; the 21mm is a bit on the large size but is very useable and might be the better idea. I wouldn't go much stiffer than 150 lb/in rear springs on a street car...

--DD