Whitline and AST Sportline 2 coilover springs interchangeable?

[sekretskwirl]

Were looking for a softer spring option than the present set-up of 40/30 were running on our Newage '02 WRX. Our roads here in the sierra nevada of California are simply atrocious. I know you dont' make the GROUP 4's any more AND that's a shame as they were very popular in the states. Some of these had 35n in the front as I recall. 30/20 progressive w/revalving is what were really looking for. Can you help us?, thanks Danielle:confused:

[Wojtek]

Hi Danielle,

In our opinion, 40 N/mm front / 30 N/mm rear springs are actually quite soft. Our Group'4 kits had 50/40, and frankly we would not recommend anything less that that. Ride stiffness and quallity is dependant on many factors, including spring rate, dampening forces and shock absorber design, set-up and configuration, and operating travel range. Getting this mixture correct is not an easy task. However, get it wrong.....

Ride height is critical here.
First, there needs to be adequate suspension travel for a given load and spring rate. Secondly, the ride height must be adjusted in such a way that there is adequate compression and extension travel.
If the ride height is too low, the suspension will prematurely bottom out on the bump stops - causing a harsh ride, loss of grip and erratic handling behaviour.
If the ride height is too high, the suspension will prematurely bottom out on the extention stops - causing same problems.

With regards to spring rates, I would suggest that they may be actually too soft already. A softer spring will compress more then a stiffer spring under the same given load, therefore, it needs more suspension (spring and shock) compression travel.
If there is inadequate shock compression travel, see above.
If there is inadequate spring travel, the spring will completely close to solid, increasing spring rate to infinity.

Therefore, I would suggest that you investigate your current suspension set-up and check for adequate suspension travel, appropriate ride heights, and adequate spring travel.

Hope that this helps.

Regards,
Wojtek.

[sekretskwirl]

good points. I notice today that the fronts have minimal travel (7 coils) and the rears look to have plenty of travel 10 or so coils. I was under the impresion the front and rears on AST WERE interchangeable..that' what the boys at POWERSTATION and SCOOBY NET stated. They sure dont look interchangeable. thanks for the input Danielle. ps why did you stop making the GROUP 4's? They were just gathering a CULT FOLLOWING in the states seroiusly you need to make something similar but w/3 way adj