Can different manufacturers' springs be used as long as you get the diameter and length right? I'd like to expand my options.

Got Tein wagon coilovers which came with 5K (280 lbs) front/3K (170) rear springs. Bought them for daily driving but have gotten into track sessions at locations like Steets of Willowsprings and Buttonwillow. The springs are soft for track sessions and am not holding camber on sharp turns at high speeds. Gots lots of other suspension tuning bits installed (front and rear swaybars, camber/caster plates, sticky tires, etc.)

Don't have the funds for new coilovers right now, so I want go up to stiffer springs without revalving. Tein says springs can be bumped up 100lbs without revalving. Next jump is 6K front, still waiting to hear from Tein customer service on what the jump can be for the rear. Rear requires a special spring. Might be 4K or 5K.

As long as the spring is the proper diameter and free length, it will work. Eibach, Carrera, Hyerpcoil etc. all make standard springs in various lengths and diameters.

Chris H.
Tein Flex on '04 STi

Many of the coilovers for Subies use 65mm x 200mm springs, which are interchangeable with 2.5" x 8" springs - readily available from Eibach, Hyperco and others for $50 each or less.

Note: Tein's price for springs is only $50 each, which is pretty competitive.
http://www.tein.com/stsp.html

Stock spring sizes for various Tein models:

RA - 65mm x 200mm F/R
Flex - 70mm x 175mm F, 70mm x 200mm R
SS - 70mm x 250mm F, 70mm x 225mm R
SS - 70mm x 250mm F, 70mm x 225mm R

Tein doesn't list Wagon fitments for Subaru any more, so I'm not sure what spring size was originally spec'ed on your Wagon coilovers.

-Steve

RA - 65mm x 200mm F/R
Flex - 70mm x 175mm F, 70mm x 200mm R
SS - 70mm x 250mm F, 70mm x 225mm R
SS - 70mm x 250mm F, 70mm x 225mm R

-Steve

So the springs on the RA's are interchangable??? If that's the case I might get the RA's and switch the springs front to back for AutoX without having to buy different springs..

So the springs on the RA's are interchangable??? If that's the case I might get the RA's and switch the springs front to back for AutoX without having to buy different springs..
Yes they are. Same length/diameter front and rear. :)

--kC