tade256

I'm planning to replace all the rubber bushings on my Evo X in the off season with polyurethane. I believe I found everything (assuming the rear upper control arm "normal" bushing is the same as the equivalent front LCA bushing), except the rear to arm (control link, lateral arm) bushing.
I found a bunch of options for the 9:
- Whiteline [W0588] - link
- PowerFlex [PFR44-115] - link
- SuperPro [SPF2063K] - link

I need the same for the X
1. Would the 9 bushings work?
2. I did everything I could to find one but failed... if you know such bushing for the X please send me links. I found traces that AMS may have had one but even if they had, it's long gone
3. I'm pretty determined to replace everything but I'd like to hear opinions on the benefits of replacing that specific one. I'm doing autocross locally in STU and there's a very competitive IX ahead of me by a couple of tenths so every small thing is starting to matter at this point

Complete toe arms is not an option, I already have adjustable LCA and the rules allow only either LCA or toe arm in the rear. Also it has to be polyurethane, spherical is not allowed.

RobbieOh

I would look at Group N Ralliart bushing from RHDJapan before going poly. But that's my preference and what I'm doing, I don't like poly.

What other suspension things have you done? What spring rates/sway bar(s) are you running? I also run a Evo X in STU down in FL

tade256

Thanks! I have heard about the Ralliart Group N bushings but was under the impression they were discontinued and not available anymore. It looks like RHDJapan site has bushings for the front LCA and rear UCA but not the trailing arm and toe arm.
I found this though but it's not legal in STU.
Why do you prefer the Group N ones over poly? I don't have experience with either so I'm open to any advice and wisdom
I only drive the car to races and back so comfort, NVH and even durability is not a factor. I also do SCCA Time Trials in T3 when time allows, not nearly as often as I would like to...
Regarding my suspension / tire setup, this is what I have currently:

• Ohlins DFV from Works revalved for 11k springs, front and back
• Hotchkis 32mm Tubular Rear Sway Bar usually on middle settings, occasionally on hardest
• Hotchkis Rear Sway Bar End Links
• Whiteline adjustable rear lower control arm
• SSR GT-X01 wheels 18x9.5 offset +22
• Nankang CR-S tires 265/35R18

Alignment by Gran Turismo East:

• front caster: 4.1 / 4.4
• front camber: -3.4 / -3.4
• front toe: 0.01 / 0.00
• rear camber: -2.3 / -2.4
• rear toe: 0.00 / 0.00

kikiturbo

Stock EVo bushings use spherical bearings (encased in rubber) in a lot of places (like rear bushings for the front arms, rear lateral lower arms in the rear, trailing arms.. etc). GrN bushings use the same but with harder rubber and have no cutouts that provide more comfort in some cases (like hitting a pothole)

GrN bushings also are engineered to run in some real tough conditions...

tade256

Thanks, but as I understand certain Whiteline and SuperPro bushings offer the same feature, but they encase them in poly instead of harder rubber.

My question was specifically about the bushing that's in the chassis (inner) side of the rear toe arm - I couldn't find a poly bushing there for the X, only for the IX. That specific bushing is not spherical as far as I know, but this is where I might be wrong.

For completeness, here are all the suspension bushings I found may worth replacing. I'll probably go with SuperPro but Whiteline has them as well:

• Front LCA
  • SuperPro Duroball Inner Rear Bushing for Front Lower Control Arms [DURO3441K] - maperformance - TODO: Check if STU allows offset bushing here, go with the concentric one if not.
  • SuperPro Control Arm Bushing Kit [SPF2418K] - maperformance
• Rear UCA
  • SuperPro Rear Upper Arm Bush Kit [DURO3737K] - maperformance
  • SuperPro Control Arm Bushing Kit [SPF2418K] - maperformance - same as front LCA hopefully
• Rear Trailing Arm
  • SuperPro Lower Rear Trailing Arm Front Bushings [DURO3725K] - maperformance
• Rear Toe Arm
  • ???

While I'm at it I'll also replace the power steering rack bushings and the motor mounts.

kikiturbo

no, inner toe arm bushing is hard rubber from stock... I would probably leave it alone unless you can go full spherical..