Ground Control spring rates?

[robgoesvroom]

Yup. HWY 9 is the road of choice when bedding in brake pads, testing out tire pressures/spring rates pre-track day...

Its such a nice road! My friend took me in his S2000 on 9 to skyline to bed in his brake pads/calipers. Maybe you've seen/met him, he's got a silver S2000 on Wedsports, J's wing, and more recently a black hardtop (Edwin). We had adventures with a 996tt and a 335d, good times.

[Chris916]

Another vote for 550/750, but I ran a 22 up front, with no rear bar.

^Yea i ran with the rear bar disconnected at AutoX but would connect it for track. Works out great that way.

[race2win]

OP please answer what Jean is asking to better clarify. Are you planning on keeping the original Bilsteins sport dampers?

It sounds like he is buying the complete set-up that GC offers for E30s, which includes off the shelf Koni Sport SA shocks/inserts. I agree with others, the reason they insist on the softer rates is because the standard shock valving cannot keep up with anything higher. In order to run higher rates, revalving the shocks would be in order, something GC does not do IIRC (they only revalve their own Advanced Design shocks I believe.) They should be able to send them out to Pro-Parts or some other Koni rebuilder prior to assembly though, I would enquire about it.

I intend to run higher rates myself, but I am going with custom re-valved shocks to match the spring rates I want to run.

[Toadleg]

So somehow me and gc had some miscommunication. He was trying to give me a street able set up. Now they are suggesting for a more track specific set up to run a 600f and 800r and they will have the shocks set up to work with that. I plan on pulling the rear sway out for autox like suggested and play around with different front sways to find what works best. So now the q's is do I go solid sub and diff mounts or stick with the poly bushings? Thanks again for your experienced responses

[joshh]

In regards poly bushings. Stay away from them if you can. Poly crushes and does not "rebound" back to it's original shape like rubber does. Either go with rubber,solid or delrin bushings.
I'd go with their recommendation. It's close to what other members are suggesting and if it's not quite right for you, changing the springs is cheap.

[Toadleg]

In regards poly bushings. Stay away from them if you can. Poly crushes and does not "rebound" back to it's original shape like rubber does. Either go with rubber,solid or delrin bushings.
I'd go with their recommendation. It's close to what other members are suggesting and if it's not quite right for you, changing the springs is cheap.

Thanks I didnt know that about the poly bushings

[joshh]

Thanks I didnt know that about the poly bushings

It's not an all or nothing thing. Some poly in certain places has worked well for people. Usually the larger pieces and with a harder durometer don't fail as often. I've used it enough now and had enough failures I just don't trust it anymore for pretty much anything.
Poly usually fails all at once not over time, from my experience.

[Toadleg]

point noted. Ive been leaning toward the solid bushings but not sure. I dont want to just do what may sound the best but be the best for the cars handling. I need to do more research on the subject. All suggestion have been greatly appreciated. Any more tips keep them coming thanks

[bwawuz02]

Anyone running GCs on a 318is? they have my E30 M3 5-lugs right now and I'll be picking them up in April. Should the spring rates be that much different for the M42's lighter weight?

I think I wanna go with the 440/625 that was mentioned earlier. Anyone driven on their new hybrid camber plates?

[Philo]

The weight and placement of engines on 318s are much different. The numbers you have posted should be plenty.

[bwawuz02]

I just looked up the rates they have advertised and compared them to a lot of spring rates from Dinan, Alpina, H&R, etc. It looks like the 375/650 might be more fitting compared to the rate/split those tuners chose... What do you guys think?

[Philo]

It's hard to base a comparison on those numbers. Mainly due to the difference in spring type. GC springs are linear while the H&R/Dinan/xxx are progressive. They don't offer a consistent force to measure front to rear ratios.

[Jeff2886]

Last year i ran 550/750 gc's and it felt great. My car has an M50, fully gutted, 22/19 swaybars, about -3.5 degrees of camber in the front and roughly -3 in the rear, and was on 245/45 RA1's. The car was extremely neutral on track with 0 understeer and the perfect amount of oversteer. I feel like the rates could be a bit higher but i will not be changing untill i go with a more expensive coilover set up.

I've been meaning to ask you about this for a while!
I need to order my parts from Perry Auto but I wasn't sure which spring rates I needed. I won't have the beefy M50 in mine though - it will be interesting to see what happens.

[!kid]

Another option for shocks if running high spring rates would be the turner j stock shocks.

[Toadleg]

So I got my gc 600f 800r set up in with solid diff and solid sub mounts and i ended up getting the hard poly rear trailer arm bushings with IE new camber toe weld in adjusters. Now im breaking in the shock as told for a 100 miles than will go to the track to test but on the street its not nearly as harsh of a ride as i was under the impression it would be. I could easily DD this set up.[IMG][/IMG]