FC Suspension setup -- Spring rates?
 

Hey!,
I've got a 1990 that I'd like to do some suspension work to. I asked PaulyDee what his setup was (he's apparentliy got his car figured out pretty well :-)), and he said he's got:

Ground Control Coilovers, 7" front springs @ 425lbs , 6" rear springs @ 275lbs
Camber plates; 2.75 degrees negative camber / 5 degrees positive caster (front)
RB rear sway bar w/ adjustable links
stock front sway bar
Trust front strut bar
Cusco rear strut bar
KYB/AGX shocks
225/50/16 Toyo RA-1's

What does everyone else think of this setup? I am most definately not an expert on this, but would having slightly stiffer rear springs help matters? How stiff a ride will this give me? I'm only 17, so I don't mind a bone-jarring ride with slightly better handling in return :).

My car has 17x7.5" wheels, should I make any changes to compensate for the lower profile tires?

Thanks in advance!,
Manolis

1990 NA FC (TII conversion underway)!

A l m o s t t h e r e :D

^bump^

what are you setting the car up for? autocross? track? whats the track like? long corners or short sharper corner in which you need more bite outta them so putting power to the ground is more important?

autocross set up seems to be 400lb fronts and 275lb rears.

Most of my stuff will be on closed sections of road and on a shortish race track, i am running 500lb in the front and will soon be running 300lb in the rear - just have kings springs on factory shocks in the rear at the moment.

I have racing beat front and rear sway bars with the adjustable end links
locally machined/manufactured rear camber adjuster
racing beat rear toe eliminator bushings
front camber plates
front shocks are fully adjustable koni race shocks and the rears soon will be too
am running on 16x8 with 215 dunlops slicks

I had those spring rates, but found them to be more of a street/track compromise. I'm switching to 550's in front and 350's in rear - although I haven't had this setup on the track yet. I'm also going to use the RB front sway bar and end links, and a stock rear bar. Most of the time I'll probably just have the rear bar disconnected - that helps reduce some of the FC's understeer.

I'll be driving around on the street most of the time, but I also plan on some Autocrossing. I also enjoy the local mountain roads ( 30-50mph corners ?), so it'd be nice if the suspension worked out for that as well.

Are the 400 / 275 spring rates pretty good for all-around driving with the occasional track day, or are they too <stiff / soft> for effective handling in the mountains / around town?

Thanks for helping me figure this out -- as you can tell I'm pretty new at the whole suspension thing :)

I think 400+ front is pretty crazy for full street. if you're in the middle of a corner and hit a decent size bumb your car will be airborn sideways... not good. however I've never driven on them so I can't say for sure... but stiffer susp is only good on flat, non bumpy roads IE track. for bumpy roads you have better traction with softer springs.

FYI, stock is 150lbs. and eibach, ST, RB aftermarket springs are around 180lbs. you do the math :) it's ALOT stiffer.

that said I'm going to be getting the 350/225 setup from k2rd very soon.

The track i will be on it only just over a mile long and has no sweeping corners, on the other tracks in NZ i'd be opting for 550/350's are they all have at least one fast sweeping corner in which i'd be holding around 180kph or more

Scott -- What kind of driving are you going to be doing? I wasn't aware that the stock springs were only 150 lbs -- I guess 400 may be a bit too stiff for messing around in the mountains / city streets.

Do you have anymore info on the k2rd setup? My end goal for the car is to make it handle as well as maybe an FD on eibachs (I got a ride in one the other day... incredible! What'll it take (with respect to spring rates for around town / mountains) to get to this level?

Thanks!,
Manolis

400/275 is really stiff.&nbsp Aftermarket stock-type replacement dampers BARELY can damp these springs.&nbsp I don't know why you want to go stiffer; stiffer does not necessarily mean better.&nbsp How do I know?&nbsp I run these on my FC...

You ever drive an E36 M3?&nbsp BMW runs very soft springs, but their suspensions are very nice for stock suspension.



-Ted

IMHO swaybars, camber, caster, toe in/out and tyre choice have more of an effect in the cornering than the spring rates.

i dont think people should be running "stock type" aftermarket dampers with those spring rates anyway. they are racing spring rates which shold be coupled with racing type shocks.

RETed, what springrate do you suggest for a daily driven car that will see a lot of high speed runs, autocross, road racing and dragracing.
Basically an all in one.

If you can handle the stiffer stuff, the 400/275 will probably make you happy.&nbsp You mention the serious racing stuff, so I would recommend this combo myself.

Ground Control runs a slightly softer set-up 350/225 (I think?) that they recommend to FC owners now.&nbsp Too many complained the old recommendation (above) was too bone-jarring. :D




-Ted

I ran the old-school 400/275 setup for a long time on the street. Sure it was stiff, but it wasn't too bad.

What are they reccomending for lengths now? Before it was 8" front and 10" rear, which are both WAY to long. I use 6" front and 7" rear.

The front ride height is a problem if the long spring length / high spring rate combinations are used with shocks that retain the stock spring perches. To get a reasonable ride height you have to use the shorter springs or do something with the spring perches. It seems that many people are using the 6" springs in the front to get the ride height down.

Rls

I use the Ground Control recommended 350/275 set up on adj. Illuminas on my TII and for the street they can still be a little stiff. They do not however over power the shocks so your range of dampening settings are useful. I also autocrossed and road course driven on them and even though they were somewhat soft for those applications, the comprimise was reasonable and the balance good. Still some understeer on sharp slow corners. As long as they don't bottom (they have in the rear from a big dip on a autox course) they are a good choice until the car is dedicated track use.

How does the ground control adjustable springs work with the Tokico HP struts? Is that a good setup?

What's with all the different F/R combos? Pauly Dee is using 425 / 275 F/R rates, while nd4spd is running 350 / 275. Won't Paul's car have MUCH more understeer than nd4spd's car?

Somewhat confused...
Manolis

One more Q....
What is the ride height as compared to stock when using the different length springs?

What, for example, would 7" front / 6" rear give you?

Thanks!
Manolis

Nope, softer in the rear will make it turn better. Same reason a lot of guys disconnect the rear sway bar, to get rid of the FC's natural tendency to understeer.

In general you are correct. But Tires, Shock Rates, Sway Bars, Ride Height, Weight Dist and probably 1000 other things contribute.

Rob

as a general rule of thumb, the rear sway bar keeps the front end level while getting outta corner after the apex and the front sway bar keeps the rear end flat while going into corners.

camber, caster etc etc all effect the set up too