Hi!

Here the story, I ran AGX and sportlines for 2 years with polyurethane bushing and a swamp 22mm rear swaybar comptech kit. The car feel nice on the road but for the trak, lapping and autoX (wich I'm now addict for a year) it's not the best set up... So I decided to change my setup for something better on the trak. I'm changing the set up cuz there is something I don't like on the car... The F/$&??& front push to much! Too much understeer... I would prefer more oversteer and less diving on hard braking...

I bought 4 koni yellows and now I need your knowledge about the coils... I have 4 differents idea but I'm not sure witch way to go...

H&R race?
H&R sport?
Progress witch I dont know a lot about..
or finally a groud control coilover but there again what spring rate to choose... And what about the spring rate of H7R and Progress?

Any help will be appreciated! Thanks!

 

I had H&R Sports/Koni on my car before moving to Ground Control. H&R lowers way too much and the springs are extremely soft. I do not recommend that setup. I've driven an EK with H&R Race/Koni, while the setup felt fine, I would go with Ground control, because it is more versatile.

GC Uppermounts
GC Coilovers
Eibach 500lb/in Front
Eibach 600lb/in Rear

 

I like the GC's too. 550 in the front and 350 in the back is what I run. I have a decent rear sway.

Tires are the single most important improvement you can make. What tires do you run?

 

Is 500 isin't too stiff for the street... That my daily driver... Anybody knows about Progress?

BTW my tire are ok. I own RS2 for STS class and Pilot sport cup for SP...

My prob is my front... Pushing hard in front...avoid my car to rotate... So I need stiffer rear... My Sportline is 450f/225r... So I thought of something aroud 350f/450r or 400f/500r... But i'm wondering if 450r++ is drivable on the street... Solo is my hobby not my job...I'm not professional, so I need my car for daily driving. Still I want the best I can get...

 

I daily drive my car with those rates. It doesn't bother me but, everyone's different. I find the shock stiffness does more to hurt the ride than the springs them selves. The roads around here aren't too bad. If you live where the roads are crappy, it might be too much.

With GC's it only takes an hour or two at most to change springs. You don't even need a spring compressor since they're loose at full droop. It's easy and relatively cheap to play with spring rates that way.

 

I'm not too familiar with coilover since I never own some and I'm trying to understand... I understand what spring rate change on car's reactions... But how does the ajustement works?

When you say you can play with spring rate, how does it work? Let's say I order 350/450, does it mean that I could change it to 300/400 or even 400/500 by changing height and play with the stiffness of the shocks?

 

What I mean is, you pick some rate, install, drive around and if you think you need more rear stiffness or less, you buy different springs and stick it in there. The springs themselves aren't that expansive. They're easy enough to change, changing them for a track day or even at the track isn't that big a deal.

As for the shocks, I have mine set for minimum damping on the streets and the ride's exactly the way I like it. It's firm but, doesn't beat me up. When I go to the track day I stiffen them up somewhat though I haven't felt the need for full stiffness.

You can't change the spring rate by adjusting the coilover spring seats, you just change it's height. The spring rate is inherent in the spring, the wire it's made from, the thickness and number of coils.

A nice number to have is "55". It's what you multiple times a KG rated spring to get the lbs/inch. So, a 6K spring is 330 lbs/inch.