View Full Version : Suspension and tire suggestions ST185

07-13-2011, 04:18 PM
OK, so here's the deal. I've had an ST185 shell with perfect body (no rust, no dents or scratches) and interior sitting in the back yard for 8 years. The car is 100% stock, and I am about to fully rebuild it.

I've got the powertrain for the most part designed/figured out, and expect the engine to have an output of about 350-400 horsepower. with RC/CS tranny and Torsen LSD. I have 7th gen rims waiting for the car but may switch to 17" in the future.

When I purchased the car, I was going to jump right into it and purchased a number of things for it. Including a the last set of TRD/Toyota Technocraft Tarmac springs in the warehouse in Torrance. They've been sitting new in the box in my "parts room" for 8 years...

The vehicle will be used for typical street driving, some canyon runs, and a rare track day. I'd like a quiet suspension that doesn't rattle or clunk going over speed bumps

Now that I've given some back-story, here are a few questions.

What bushing sets are available for this chassis? Are stock available? any poly bushing kits?

Is caster/camber adjustable on this chassis from the factory? If not, are there aftermarket options? Camber plates, or do I have to deal with "crash bolt" styles of strut/spindle bolts?

Should I stick with the TRD tarmac springs, and go with some aftermarket strut insert. I am sure the struts would have to be custom... does anyone have recommendations for strut inserts, and specs?

Or should I just go with a set of coil overs... I have access to corner scales, and alignment equipment, but I really think they would be too much hastle for a street vehicle... also to get a set of coil-overs to be quiet for street use is a pain.

Thank you all for your input. Cost is really not an option, as this is an "over time" build and I can aquire as funds become available

07-14-2011, 02:41 AM
Oh man, so much to go with here...

Um... well bushing kits are available. I got mine from Toyheadauto.com but you might be able to find them cheaper elsewhere.

Camber and caster are not adjustable from toyota (well some camber from play in the bolts). I know noltec used to make camber/caster plates for the ST185 but it seems like most of the stuff available now is camber only. I ran Ksports on mine but I had to machine out the sleeves to work with OE sized struts.

I'm not familiar with the handling of the TRD springs but chances are they're made by someone else. I run H&R springs on my daily with off the shelf Koni yellows and it's been a lot of fun for very little money. Not really track ready (not enough spring) but definitely good fun.

Alignment matters! I've made huge jumps in time by playing with alignment settings, I mean it, HUGE.

Remember though, everything is a compromise, fast on the track is going to be harder to live with on the street, you'd got to pick where you want it softer vs sportier. On my street car I went with relatively soft springs, good shocks and an aggressive alignment spec. So far I'm very happy with it on a day to day basis (pisses me off sometimes on the track but that's as much from the gutless wonder 5s as anything).

07-14-2011, 02:46 AM
Oh yeah, tires. Really depends on the life and the driving conditions you'll encounter.

If it rains a lot, I'd recommend the Dunlop Star Spec or Toyo R1R. No rain and hot weather Hankook RS3 or Kumho XS (Note: The XS need to be HOT to stick; RS3s are good warm but amazing hot). Honestly there are always new super sticky street tires coming out. Hell, you might be happier running a softer tire than that, like say Toyo RA1s or something in that range (Race compound but with SOME life).

07-14-2011, 03:11 AM
welll the TRD/Toyota Technocraft are not the TRD/Swift that are produced now... they are TRD Japan springs made by Toyota Technocraft also known as the "low ride height" springs (as they also sold gravel springs which lifted the chassis)
The spring rates for these springs are:
43.1 N/mm front
38.2 N/mm rear

Not sure how they compare to your springs, but you mentioned a 5S, so I am assuming that you're not the same chassis anyways.

Thanks for the bushing suggestion, Looks like they have everything I will need there.

I'll probably just stick with camber plates front and rear, Use the TRD springs I have, and as for struts, get some custom valved inserts. I'm also going to have to find a strong rear adjustable bar to help make the car rotate.

07-14-2011, 06:22 AM
I am not on the same chassis, however setup for a FWD is not very different from an AWD setup; loose is fast.

Get the plates, use the springs, get some bars, and get some Konis race inserts for the additional valving. 8610-1437RACE for rebound adjustable only (rated for up to 700lbs/in) or 8611-1437RACE for the double adjustables (Being a McPherson strut assembly you just have to find the right size insert and shorten the housing to fit).

Honestly that spring rate should be pretty good for a street driven ST185, being that it's a heavier car it shouldn't feel too stiff.

07-14-2011, 06:52 AM
I was looking at the Koni's you suggested. are you running the same strut at all four corners? also, for the double adjustable struts, it states to machine a hole in the bottom of the strut housing to access the adjustment screw.... in the past when using strut inserts, I have filled the strut body with a light oil to transfer the shock's heat to the housing... if I drill a hole in the bottom of the housing, that's not possible. have you had any problems with the shocks becoming less effective with the heat changing the viscosity of the internal shock fluid?

07-14-2011, 07:04 AM
I run off the shelf konis in my street car. My autoX corolla is running the single adjustable Konis up front and QA1s in the rear. I don't imagine it's a problem running the stiffer valved konis all around.

Being as I haven't had to drill a hole in the bottom I can't say whether that'll be a problem or not but I highly doubt it. Honestly, unless you're familiar with how to tune compression settings I'd stay away from the double adjustables as you'll probably find yourself making the handling worse rather than better (rebound is MUCH easier to tune).

The 8610/8611 struts are some of the most commonly used shocks for autocrosser and road racers world round (probably the best bang for your buck). You could always spend more for Penskes, Ohlins, Motons, ASTs or JRZs. Those generally are purchased as a coil-over kit and run between $1000-3000 a corner.