Those of you running the Steeda adjustable coilover suspension
what springs rates have you picked, and what did you set the tokico shocks/struts to?
it'd be nice to know the weight of your car too, to better judge the spring rating..
starting with me.. i got 225lb springs all around, and i absolutely hate the rear..
car tends to bounce and jump over every road imperfection regardless how soft/hard i set the shocks.
i'll be weighing the car soon on all 4 corners and look into swapping out the rear springs
Hi G.T,
I've been playing with the Steeda coilovers since they came out. The internals AFAIK are the same as normal D-Spec S197 struts and as such will have the same limitations as far as spring rates they work well with. You can't really use more than about a 350-375lb spring on the front colivers because there is not enough damper force to control a 400lb spring well. I've never reached the limits of the rear dampers because any rate much over about 250lb/in has the axle bouncing all over the road due to the particular weight of the rear axle, wheels and tires.
In your case you simply have too much rear spring rate
compared to the front spring rate and this is making your car bounce over the road due to harmonic interaction between the front and rear suspension from many different factors like damper force, sprung and unsprung weights, wheel base etc. To tame this bounce you need to get springs that do not cause these reactions, reduce your rear spring rate!
The Steeda Sport springs are 225lb in front and 165lb at the rear and Steeda's Race springs are 250lb in front and 175lb out back. The Sport and Race springs are both linear rate springs. I found the Race springs to be a bit soft for agressive street driving and the Sport springs even more so. But for a reasonable handling and riding street car suspension the regular Steeda Race springs with conventional D-Spec struts or Steeda coilovers if you don't go too low are a very reasonable setup.
FYI, Steeda actually did the developement work for the D-Spec damper rates for Tokico on this car using their own production springs so you know they will work well with each other. You already have two pairs of 2.5" I.D. 10" 225lb/in springs and if you are O.K. with the front rate I suggest that you buy a set of Hyperco 2.5" I.D. 10" 185lb/in springs for the rear axle. You can buy them from Steeda or order them from about 1,000 race suppliers on the internet for about $60 or so each. Maximum Motorsports carries them and usually has them in stock ready to ship.
Just be aware that using these modest spring rates means that you cannot lower the car much and still retain a good ride. The S197 chassis likes to be low on the race track and with much higher spring rates works very well. But you are driving a street car no matter what you want to think so if steering feel, front grip and ride are important to you don't reduce ride height more than an inch from stock or stuff happens to the geometry that is less than optimum. The car will bottom out excessively if you reduce your ride height more than an inch on either end, this is what causes the ride issues almost everyone has but does not quite recognize.
Also note that like many racing coilovers the springs will not be seated on the spring seats if you get airborne if you set your ride height at a reduced ride height due to the increased spring rate and reduced spring compression. This is less of a problem for a race car because the damper tech can just stuff a few droop limiters inside the dampers and the springs will no longer hang loose in the seats but for use poor folks loose is what happens unless you go dual springs or helpers.
HTH!
