I've been deciding if i want to get a set of ground control coilovers and was wondering what spring rate did you get and what was your reasoning behind choosing that spring rate? How low have you gone with your setup? How low could you go and still have control and be some what tolerable? How hard is it to lower and lift back up? What struts/ shocks are you using? Are you satisfied with your setup? thanks.

 

I know cjv (Chris Vurnis) here in California is running GC/Koni.

Not sure how long you can go, but typically a drop of more than 1.5" on Nissans is a receipe to completely screw the handling.

Shocks... use Koni's. The "basic" GC spring rate, IIRC, is 250lb.... which will kill Tokico's quick, will kill stockers even faster.

Not sure about adjustment, but on the G20/200SX it's pretty easy. Seen some of the SE-R guys do all 4 corners at car shows in under 20 minutes including removing the tires (if needed).

 

hey,
the default on the Ground Controls should be 450lb in front and 300lb in rear. adjustment is pretty easy on all Ground Controls. Loosen the collar with an allen key and turn the collar up or down. I lowered mines about 3" and the suspension bottoms out often, causing very poor handling on bumpy roads and a broken back all the time...im using Koni adjustables with my Ground Controls. The only thing i dont like are many people have probs with noises from the GC's including myself. And i feel the Koni's should have been made with a shortened body to allow for more suspension travel.

 

I choose 475 front and 350 rear. I am all the way down, about three inches, and am on stock GXE struts with about 62k miles on them. My ride is acceptable, I'm in need of replacing struts now. In reply to BrianW, you can ask Kaleb from Dallas or Ming from Atlanta or Matt from Tulsa as to how my car handles and rides. My car has virtually no body roll, and it does take bumps pretty good. There are a few craters and speed bumps that my car will hit bump stops, but for the most part, its very acceptable. EricGP also has GC coil-overs on stock 97 SE struts and he is down 2.5 inches. His ride is almost like stock. As far as the noises, I have experienced them, and they come and go. EricGP has never experienced any noises since he installed them.

 

Hello:

I got ground controls with the following setup:

375LB/IN front
350LB/IN rear
Stillen 2 way RSB (set to stiff)
Polyurethane FSB bushings.
KONI sport struts (75% stiff rear, 100% stiff front)
SSR Integral 17"X8" 235/45/17 Bridestone S-O2PP
-.4 degrees front camber... 003" toe-out.
Bottom mount camber bolts...
44PSI front, 37PSI rear...
2.00" reduced rear height from OEM
Approx. 2.25-2.50" reduced front height from OEM
Progressive rate bump stops (which I rarely if ever hit)
FSTB and RSTB


My feeling is that the polyurethane bushings on the FSB are like adding another 25-50LB/IN on the springs. I am set up 2.00" below the OEM ride height...some folks have said that those bushings didn't make a difference on their cars but it really did on mine....

I had noises that came from the rear of the car... You have to get an extra polyurethane upper strut mount for the rear suspension... Because the rubber ones compress so much that the rear top-hats bang into the body of the car...
I know a guy who had problems with his rear stabilizer bar hitting the beam axle but took care of it by sliding the RSB clamps on the trailing arms back a little bit to get clearance of whatever it was his bar was hitting on the axle (not sure exactly). I've had no problems with noises on the front suspension...

At one point in time I was pushing over 3.00" below OEM ride height... But I found that was just too hard a ride for me and caused too many interior rattles... but at that time I also had -.8 degree camber. As long as the road surface was smooth, I could really go amazingly fast in the turns... With the higher ride height, I can go "fast" instead of "amazingly fast"... But with rougher roads, there seems more stability in the turns with the higher setup... Either way I have never had noises from the front end and don't anymore with the rear with my current setup...

When I reduced the front camber, I increase the struts from 50% stiff to 100% stiff and the handling going into a turn doesn't seem diminished any but the ride quality with the lower camber is a lot smoother... KONIs are pretty forgiving too as long as you don't slam then low...

But those Potenza S-O2PP tires are just awesome... they stick like glue and the tread pattern is really good in the rain too.. but they cost big $$$... $900 for a set and they last me about a year...


Another problem with going so low is that the RSB clamps will contact the undercarriage of the car... I am going to have a local suspension shop drill the trailing arm and clamps to changing the bolt position and then shave down the upper side of the clamps so they don't protrude so high above the arms... It should yield an extra 1.5"-2.0" inches of travel which is important for having rear passengers or cargo...

I run the inflation pressure at 44PSI on the front (maximum allowable) because the tire loading info states 1433LBS@44PSI max pressure... Each front tire supports about 1000LBs... throw in whatever weight transfer effects exist in the turns and that gets close to the maximum load rating of the tire... I have tried many times with lowering the pressures but then the tires start howling more in the turns at lesser speeds and the steering isn't nearly as sharp....

A lot of how a car feels is how much throttle you give it through the turn... I got an automatic tranny... I take the exit ramps usually in 2nd gear (13MPH/1000RPM)... I enter the turns a little slower than the full capability of the car and then I just give it a little throttle through the turns as necessary and that really helps balance out the weight load on the tires... the torque output of the motor transfers weight to the rear of the car and that helps out nicely on a FWD car where more weight is on the front wheels...

With the tight springs of coilovers, you can take the springs rates as a rough guide to calculate how small amounts of suspension movement translate to substantial weight transfer even with just a little bit of acceleration through the turns...

Based on this, I can tell you that I can't make the car feel as good through the sharper turns in 3rd gear or Overdrive... Good thing about my automatic is that 2nd gear is strong from 30MPH to 75MPH (top speed is 85MPH) so it is very well suited for brisk runs along the mountain roads... I just leave it in 2nd gear and wind it out on the straight sections and half my braking just comes from the motor itself when I lift the throttle... No shifting to think about.. just keep your hands on the wheel and a steady right foot and think about the turns...

Are you guys with the stock struts bouncing up and down all the time? I'd be surprised if you're not with those tight springs...


My humble two-cents worth...

 

go to motivational.net and talk to i think his name is jeff saiki, b/c he told me they can lower the spring perch to allow an extra inch of travel, sounds like thats what you want

 

hey Chris


i was wondering on the rear, those rubber bushings that compress too much. What did you replace them with? i have this same prob too and its really annoying sometimes. thanks, i appreciate the help!

 

you out there Chris??? was wondering on what bushings you used on the rear for your Ground Controls....thanks