00-09 Legacy/Outback rear spring rates?

[FerGloyale]

Hey all.  

Request to those in the know about spring lengths and rates for 00-09 Legacy/Outback rear ends.

 

I am using 03 outback wagon rear springs for FRONT springs on this project.  Anyone know what the specs for length and rate are for these?

 These springs may be just too stiff.  set it down on it's own weight and it barely if any weighs down the front end.  I have a feeling it would be "topped out"  under even the lightest throttle.  I would like it to sit more in the middle of it's range of travel.  

So my question is how do other springs from Sedan models, Non-outback models, and maybe rallitek options all compare in length and spring rate?

I also have thought of trying to cut 3/4 coil off the curent springs, to bring it down some.  But shortening the spring may lead to coil bind under full compression. thoughts?

 

[Numbchux]

There are many many different variations (different part numbers, anyway). I don't know any lengths, but here's what I do know.

From my notes (honestly, not sure of the source), an Outback wagon rear is 190 lb/in.

Rallitek is 355 lb/in, which is supposedly about 20% softer than King.

 

Baja is stiffer/taller than Outback, as people use that as a lift.

 

Auto transmission usually gets stiffer springs, front and rear, than a manual.

Spring rates are probably similar between the same body styles, regardless of height (Legacy sedan vs Outback sedan, Legacy wagon vs Outback wagon).

Obviously Outback stuff is taller than Legacy.

 

When I run out of things to do (:eyeroll:), I have Tacoma Offroad bilsteins that I want to test fit in the rear of my '01 OBW parts car, and I plan to take some measurements. But it's fairly low on the list right now.

[FerGloyale]

1 hour ago, Numbchux said:

 

From my notes (honestly, not sure of the source), an Outback wagon rear is 190 lb/in.

Rallitek is 355 lb/in, which is supposedly about 20% softer than King.

 

 

 

WOW.  Only 190?  I thought they'd be at least 250.  Maybe Sedan springs would be less?  

Gosh, if they are only 190, maybe I just need to get it rolling and pound it over some bumps and see how it settles in.

What do you think about cutting 3/4 of a coil off?  

[idosubaru]

1 hour ago, FerGloyale said:

What do you think about cutting 3/4 of a coil off?  

In XT6 world, converting a 4WD air suspension to regular struts from a FWD XT6 makes the rear 2" higher than the front.  Common comments suggest that cutting the coils ruins the hardening and end fitment of the spring.  But in practice it's been done plenty of times and I've never heard of issues. 

[FerGloyale]

1 hour ago, idosubaru said:

In XT6 world, converting a 4WD air suspension to regular struts from a FWD XT6 makes the rear 2" higher than the front.  Common comments suggest that cutting the coils ruins the hardening and end fitment of the spring.  But in practice it's been done plenty of times and I've never heard of issues. 

 

Yeah that difference is because of the change in rear shock mounting on the EA/ER platform.

As for cutting, the lower perch has accommodation for the coil end.  The upper perch is flat, but the spring is flat also on that end.   So if I cut the lower end, and rotated the spring so the end fits in the notch, I don't see it being any issue.   I would cut with bandsaw, so no real heat or hardening change.  

What I do worry about is that I've got about 6 inches of shock travel.  The current roughly 12" spring, compresses to 6 inches just before coils touch.  If I cut it to 11"  then when the strut compresses that full 6"  the spring coils may touch at the bottom out point.  I do have urethane bumpers on the strut shaft, so that should soften it before the coil bind "hits"  But IDK.  I cut some random aftermarket Legacy coils to work with EA81 struts, and ran into this binding problem I am talkin about.  Don't want to do that again.

Anyhow, gonna put the trans back in the car, swap tie-rods for EJ ones, and take it for a rough drive to see how it works out after settling in the springs.

[idosubaru]

“Take it for a rough drive” - with cut springs?

Can you load a few hundred pounds in the back, maybe with one wheel on blocks, to simulate the travel where you can inspect and measure?  

I’m trying to do that with my one rear wheel rubbing but it doesn’t rub by just loading it with weight.  

What is binding? 

assumed you were familiar with the rear EA82/er27 stuff.  since cutting is common for XT6s and you asked about cutting I figured I’d point there But that has nothing to do with travel.  

[Numbchux]

Yea, when you bottom out the coils against each other, it's called coil bind, and is VERY hard on things.

 

Cutting some of the spring off, would make it easier to bottom out the assembly, but since the travel is limited by the strut, it should be less likely to coil bind at the same point in the strut travel.

[FerGloyale]

12 hours ago, idosubaru said:

“Take it for a rough drive” - with cut springs?

Can you load a few hundred pounds in the back, maybe with one wheel on blocks, to simulate the travel where you can inspect and measure?  

I’m trying to do that with my one rear wheel rubbing but it doesn’t rub by just loading it with weight.  

What is binding? 

assumed you were familiar with the rear EA82/er27 stuff.  since cutting is common for XT6s and you asked about cutting I figured I’d point there But that has nothing to do with travel.  

 

No, I meant take it for a drive as is now. Then decide whether or not to cut, or go to softer springs.

I am using these springs as FRONT springs paired with 2011 front struts, on an 84 GL wagon that previously had 8" top blocks.  With the longer 2011 struts, I am now running 5" strut top spacers. 6" crossmember and radius plate drop.