It's all personal preference I think. Generally stiffer springs are used for racing since it keeps the suspension from traveling too much. It also depends on how nice the track surface is. If it's really nice and smooth then you'll want stiffer springs but if its bumpy at all the stiffest springs might but too harsh of a ride. You already have to most important mod for auto-xing (sway bars) so the springs (IMO) just tweak the ride a little bit. My goal is to get the handling on my car to be as close as possible to my neighbors Mercedes CLK500. Granted there's a bunch of stuff the tC will never have that the Benz does but I think my setup is pretty close. The goal was to carve corners but maintain a smooth, comfortable ride. I think once I can afford the HKS coilovers I'll be about as close as I'll be able to get.

 

to kanundrum, you dont necessarily want the highest spring rate, you want a balanced set up between dampening and spring rates.

your best bet would be going with some type of pre-assembled coilover in which you can adjust the dampening.

however, you can purchase a set of koni shocks, and which ever springs you want and have koni custom make you a set, since koni shocks are adjustable.

i personally placed an order for KW Variant 2 Coilovers with custom 600/800 spring rate.

the reason i went with KW was because they have hands down the best made strut/shock, and they use eibach springs, which anyone in the racing industry will tell you, they are number one.

If i were you kanundrum, i would settle with the TRD shocks since you have them, and go with eibach prokit springs.

 

Those are some pretty extreme spring rates for a daily driven tC. Is KW re-valving your dampers to better match the rates you've chosen?

 

true, they are going to be pretty stiff but like you i will be tracking the car ALOT.

im at the track almost every month, so they will be put to good use.

BTW, the springs rates are incorrect that are located on the first page for KW.

they are actually Front=340 / Rear=455

KW said they will be adjusting them to better suit the spring rates.

also, i have ridden in a tC with 550/850 springs rates, the ride wasnt that rough, and i dont mind a bouncy/rough ride.. i dont necessarily need the smoothest ride.

hopefully one day me and you will see each other at the track, we can see who has the better set up

 

The spring rates are correct. They were converted from lbs/in to kg/mm. Conversion was done in google and I verified that they are correct.

 

I think Ill be getting some H&R coilovers when my shocks are totally gone I want something for hard track use I dont care about ride comfort.

 

damn dude...

 

would that stiffer then the H&R ?

 

Yes. That would be about 10.7/14.3.

For anyone that wants to know how to do conversions with google just type in "600 lbs/in to kg/mm" and you'll get the answer.

 

awesome how do i order

 

just remember.. stiff isn't better. you need to strike a balance. you want to get your spring rate as soft as possible for the corner weight (+weight put on by downforce) of your car. softer rate allows the wheels to follow the contour of the road better.

most likely the best result is 10% higher rate over stock and 1 or 1.5" lower height. the rest of your money can go into braces and such to stiffen up the chassis flex.

 

i have done enough research, and that is why i chose those spring rates..

the dampening will be adjusted to follow suit.

bracing will be in way of a 8 point roll cage later down the road.

 

i'll have to look for my papers on my Zeal Function-X coilovers. Gonna get the info for ya so you can put it in the chart. I'm probably the only one on this board with them. Since there were only 3 made period.

 

who are the other two?

 

one belongs to another SL member (iuno if that person still post here), the last one to my knowledge is uncalled for. the buyer flaked. if your really interested I could call Rishie for you and ask about the 3rd set in question. let me know

 

i have coilovers on order, i was just wondering where the others were.

did you have these custom made by endless? or did they happen to make a set and you jumped on it?

 

they were custom made by Endless. And only three sets were made only.

 

any updates on this list? like the HKS specs?

 

i got the megan 32 way adjustable suspension on my 07 scion tc.its sweet.if there is anything i can nit pick about it its that the rear cannot get slammed like i can in the front.i wish there was a was i can at lease get 1/2 INCH lower in the rear .i have 18inch advan model 6 on there and the wheel well is about a just under a inch above the tires.

anyone here have the megan suspension and know any idead on getting them lower in the rear?

 

I'd update the chart if ppl had any more info.