Rear Suspension Upgrades: RSB, Endlinks, Support Brace
 

Hopefully this helps some of you guys who are on the fence on installing a rear sway bar (RSB), endlinks, and/or stabilizer brace. I personally love my new setup. Very nice and stable in hard turns and corners.

PARTS I PURCHASED

1. AVO Rear 21mm Stabilizer Bar (RSB) (S2C07G1HS021J)
2. Kartboy Endlinks
3. AVO Rear Stabilizer Mount Brace (S2C08G1HT002T)
4. Mobil 1 Synthetic Grease (red)
5. (2) Kartboy front spacers

TOOLS I USED

1. 13mm, 14mm, 16mm, 17mm, 19mm sockets
2. 13mm, 14mm, 16mm, 17mm, 19mm ratcheted wrenches
3. 1/2" torque wrench
4. 3/8" socket wrench
5. 1/2"-to-3/8" adapters
6. 1/2" breaker bar
7. 3/8" 5mm hex socket
8. ramps or jack stands
9. hydraulic jack

CAVEAT: THE FOLLOWING STEPS MAY BE INCOMPLETE, SO USE AT YOUR OWN RISK!

1. Put the rear of the car on jack stands (one-notch is fine)
2. Optional: Support the rear crossmember with the hydraulic jack in case you accidentally remove both large 19mm crossmember bolts; your whole bottom end WILL fall down, so don't do that!
3. Starting with the LEFT endlink, remove the bottom bolt and nut (REUSE)
4. Remove the top bolt on the LEFT endlink using a ratcheted wrench and the 5mm hex socket
5. Repeat the previous two steps on the RIGHT side
6. The endlinks should be free from the control arms and the old sway bar
7. Remove the bolts from the LEFT stabilizer bracket (REUSE bolts and bracket)
8. Repeat about step for the RIGHT side
9. The rear sway bar should be free; slide it out between the exhaust and the bottom-side of the trunk
10. Grab the AVO rear sway bar (RSB)
11. Liberally grease the bushings and install on the sway bar
12. Insert the AVO RSB from the rear of the car, above the exhaust and below the bottom-side of the trunk
13. For now, hang the AVO RSB using just the OEM sway bar brackets
14. One side at a time! Loosen the LEFT crossmember bolt with the breaker bar/ratchet + 19mm socket
15. Remove the black circular plate between the cylindrical mount and the bolt (NOT resused)
16. Grab the LEFT-HAND (LH) AVO Support Brace
17. Install the brace using the big 19mm bolt; perfectly align the brace between the OEM RSB bracket (torque to 100Nm afterwards)
18. Reinstall the two RSB bracket bolts and spacers
19. Repeat the above three steps for the RIGHT-HAND (RH) side
20. Grab the Kartboy endlinks
21. Grease the insides of endlinks; the sleeves slide out
22. Starting with the LEFT, feed the Kartboy bolt towards the center in the following sequence: washer->Kartboy front spacer->Kartboy endlink (top)->Kartboy front spacer->AVO RSB->washer->nut
23. Reinsert the bottom bolt, feeding it front-to-back, in the following sequence: washer->control arm hole->fat Kartboy rear spacer->Kartboy endlink->skinny Kartboy rear spacer->control arm hole->nut
24. Repeat the above three steps for the RIGHT side
25. Ensure the AVO RSB, endlinks, and bracket are all properly aligned, then torque down accordingly:
26. Torque endlink bolts: 44.7Nm
27. Torque bracket bolts: 40.7Nm
28. Torque crossmember bolts: 100Nm
29. Remove the hydraulic jack, tools, people, fingers, limbs, head, and anything you don't want to lose from under car, then lower!

Nice. The bar is upside down but still should work fine.

Oh, yeah. LOL! Good catch. That was the first time my buddy and I installed it six weeks ago. I didn't realize it was upside down. I fixed it two Saturdays ago. I appreciate it!

Based on your impressions of this upgrade, does it have you looking to upgrade the front sway bar in an effort to stabilize the car in corners even more?

From what I have read, if you do the front you need to further thicken up the back to compensate for understeer.

I'm looking for an ideal setup (obviously an objective measure without any real g-meters and testing, or skidpad results) that will maintain the front sway bar. Looks like it is tough to replace and requires garage work. Like you I have an eye toward doing most of the suspension upgrades myself.

I am also wondering what made you go with the 21mm bar over the STi 19mm bar.

Thanks in advance!

You probably read that from people who don't know what they are talking about.

"ideal" is using sway-bars as the final piece in a suspension puzzle to tweak everything. Here, the 5th gen is at a disadvantage. I don't believe there are any replacement strut options out there, which makes suspension optimization even more difficult.

Swaybars reduce body roll by increasing the effective spring rate as weight shifts. With stock struts, this often makes a typically oversprung suspension much worse. Not an issue on glass-smooth on-ramps, but murder on bumpy turns you want to take at speed.

Simply tossing a big RSB on a car does not reduce understeer, it simply increases oversteer. There is a subtle, but critical, difference between the two.

If you MUST do something, the STi RSB is probably the biggest I'd go with otherwise stock suspension. I'd absolutely invest your time and money into endlinks and a proper alignment.

Just thought I'd post that I saw you at Fitness First the other night, posted it up in the Mid-A Spotted thread, you didn't acknowledge. </3

RCE made revalved Bilstein's for the 5th gen.

I do plan to add springs next year sometime. I am also reading up on the Bilsteins mentioned above.

So, the suspension won't be completely stock.

I'm going to approach this gingerly since you are an administrator.

If you add enough "oversteer' by adding a rear anti-sway bar, you can make the car more neutral. Is that not a desired outcome?

For posterity:

http://farm9.staticflickr.com/8066/8...0f2985af_k.jpg

LOL, administrator. :lol::lol::lol::lol::lol::lol::lol:

People tend to think they want more oversteer, but in reality you'll want more understeer as it's easy for the driver to be more confident as to where the limit of grip is.

:whore: for the general public.

I want some understeer if I'm doing quick left right turns like a slalom and don't want the car to come around too much.

I want neutral if I'm doing a long sweep...like an onramp/offramp

I want oversteer if I'm trying to drift with a front wheel drive car.:spin:

You can do a lot of things the wrong way, sure.

:icon_roll

As far as I have always understood it and experienced it, there are a couple of different things here.

1. If you are looking to drive with some enthusiasm, you are looking for the car to err more on the side of neutral. I have never minded a bit of oversteer when driving enthusiastically, but I don't think upgrading the sway bar to 19mm (or even 21) is going to cause the car to become a drift monster in every turn when under power. Under power being the key here.

2. That brings us to the second point. I think the caution that most manufacturers build into their cars for the regular driver is a bias toward understeer, especially in situations where the driver may lift off or brake heavily.

Given the weight distribution of the Legacy GT, I doubt upgrading the rsb to something like 19 or 21 mm is going to cause the car to begin to oversteer in panic breaking or liftoff situations.

Sound about right?

Also, to the OP, after seeing yours, I went ahead and purchased the AVO mounts for the RSB. Figured if I am going to do end links and the RSB, might as well take care of all touch points.