BE stock spring rates?

[rougeben83]

Anyone know? I'm deciding what spring rate to run on coilovers if I get them...the stock would be a good gauge as to what would be too low .

[rougeben83]

No one knows? :oops: Oh well :|

[rougeben83]

Ok, I'm going to put an estimate out there, based on spring-rates from aftermarket lowering springs, which are usually 15-25% stiffer than stock.

F: 1.8-2.2 kg/mm
R: 3.5-4.2 kg/mm

This is assuming that the are linear rates; these numbers would be the beginning of the stroke. If theyre progressive it will be going much stiffer as they are compressed; up to 4kg/mm for the front and around 6kg/mm for the rear.

Rears have a higher spring rate because of the multilink setup using a shorter coilover housing.

Again, before anyone bites my head off for doing a little math, these are just some general numbers for comparison if picking custom spring rates for coilovers or aftermarket springs.

[ten80]

Ben,

I think I remember that the springs are not progressively wound- ie. no taper to the spring or change in the coil size or distance. I did glance at them when doing some brake work. This would mean that the rates are linear. Other than that, your guesses seem to be in the right ballpark, though I'm more familiar with lbs/in units.

[rougeben83]

Ben,

I think I remember that the springs are not progressively wound- ie. no taper to the spring or change in the coil size or distance. I did glance at them when doing some brake work. This would mean that the rates are linear. Other than that, your guesses seem to be in the right ballpark, though I'm more familiar with lbs/in units.

Cool, that makes the calculations easier then. Though there are a number of lowering springs that are progressive (H&R and SYMS, for example), as a note to those looking for spring upgrades for their BE's. STI's are linear, as well as Intrax AFAIK.

In standard, the rates would be 100-125lb/in for the front and 195-235lb/in in the rear. Typically, springs are changed in 50lb. increments, so these numbers still within a small range for comparison.

I *think* the gauge limit that OEM's have for a "livable" suspension is around 1.5-2 kb/mm, which would be about right for the fronts. However, that really throws off people is the multilink setup in the rear, which softens up the perceived spring rate by a bit (I want to say by 30% like in the 05+ Legacy's, but don't quote me on that).

[rougeben83]

Ok, just to keep this all in one thread, B4 Legacies got 2.56kg/mm F / 4.84 kg/mm R.

Keep in mind the B4 uses a stiffer and slightly lowered suspension.

[OutbackGT]

Ok, just to keep this all in one thread, B4 Legacies got 2.56kg/mm F / 4.84 kg/mm R.

Keep in mind the B4 uses a stiffer and slightly lowered suspension.

Where did you find this info?

[rougeben83]

http://autospeed.drive.com.au/A_1242/cms/article.html

Pretty comprehensive.

[OutbackGT]

Nice find.

[badbasser98]

Keep in mind the B4 uses a stiffer and slightly lowered suspension.
any idea how much lower?

[rougeben83]

Hmm no definite idea, but I'm guessing around 15-20mm or so; I'm basing this on the SYMS springs that I got that are rated to drop a B4 20-25mm, while the original owner who had it on his GT reported it dropped his car about 1.5"