CSG and RCE tag-team suspension Q&A thread! Ask us anything!

[Drifter X]

Originally Posted by TwinFTW

Just another data point:

I'm also on stock Sachs performance pack car with the Pedders mounts installed but in the max negative camber orientation, along with front lower camber bolts.

I get no clunking at all and have a few thousand miles of mountain b-road driving on this set-up, no additional noises yet.

I moved mine to the negative camber orientation now and same thing. Torqued everything to spec except for the strut nut because I don’t have a strut nut socket that’ll work with my torque wrench.


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[staples323]

I'm moving closer and closer to going into NASA TT5 (HPDE 4 currently) and want to upgrade from the stock suspension before making the move to time trial.

CSG Mike posted this Questionnaire and figured I'd use it to make things easier

- What your experience level is: HPDE 4/ about 2 years track time with the BRZ and 3 years of kart racing before that
- What wheel sizes (size, offset) are on the car: 17x8 +42 TC105X
- What tires (type, size) are being used on the car: 225/45/17 Hankook RS4, may switch to similar-size Maxxis RC1 or Toyo RR in time trial
- What kind of car balance you are looking to achieve: Trying to keep the car similar balance to stock/ RCE swaybars currently, may go back to stock rear
- If there is Aero on the car: No aero/ may in the future
- If there is FI on the car: No FI
- If there are already supporting suspension mods on the car (bushings, arms, camber plates, etc.) Camber bolts. If future coilovers do not come with camber plates these will be added/ spl rear control arm is also planned.

Single or double adjustable/ no external reservoir, don't want to take the mod penalty in TT5. American or have U.S. factory support preferable for ease of rebuilds

$3-4k budget range

Thank you for any input you guys have.

[dpfarr]

I’ve a new ts and I’m thinking about bushing upgrades before most everything else.

Is there a tutorial or explanation of x,y,z does?

It occurs to me doing a transmission bushing to shore up some slope I’m interrupting might be the first order of business?

Tracking occasionally.

[Kiske]

RCE Tarmac 3 Clubsport Coilovers ever coming back for sale?

[Racecomp Engineering]

Originally Posted by Kiske

RCE Tarmac 3 Clubsport Coilovers ever coming back for sale?

Never say never...but not anytime soon. We do still carry the KW 3 way clubsport which are a little softer.

- Andrew

[Racecomp Engineering]

Originally Posted by dpfarr

I’ve a new ts and I’m thinking about bushing upgrades before most everything else.

Is there a tutorial or explanation of x,y,z does?

It occurs to me doing a transmission bushing to shore up some slope I’m interrupting might be the first order of business?

Tracking occasionally.

The driveline bushings (motor mounts, transmission mounts, rear diff inserts) are very good at reducing the slop and makes putting power down feel a lot better. Just doing the diff mount inserts makes a big difference, but does add a little gear whine.

The rear subframe inserts are another good way to make the rear feel more connected and reduce extra movement (with a little increase in noise). Feels good though.

The above probably won't reduce laptimes, but IMO can improve confidence which is still important for a variety of reasons.

Steering rack bushings (or the Perrin steering rack lockdown) feel awesome with minimal if any drawbacks. Just better steering feel. Perrin is easiest to install.

For the suspension links...here's a general (non-BRZ specific) guide:
https://www.instagram.com/p/CBQUCS9n..._web_copy_link

With polyurethane bushings, you MUST inspect them frequently even if it's a single axis rotation spot. Improper design can still lead to failures in relatively simple locations. It does happen and it can be catastrophic!

For the rear: trailing arm, toe arm, rear lower control arm, rear upper control arm. We often replace the toe and lower control arm with a whole new part that adds alignment adjustability alongside firmer bushings. I also use the STI trailing arm which is not adjustable but has a nice high quality sealed spherical bearing. All of these make a difference, but may not be 100% necessary for everyone.

For the front: front control arm (big front bushing, little rear bushing). The big front bushing is IMO one of the most noticeable from the driver's seat. There are a variety of options...the STI Group N rubber bushing is probably the best upgrade for most people. Not easy to get stateside but possible. I'll post a part number in this thread at some point:
https://www.ft86club.com/forums/showthread.php?t=142230

The polyeurathane bushings also work and can have other benefits like added caster but again I would inspect them frequently. Spherical bearing options exist but they are expensive, and most will replace the full arm at that point and get some adjustability + spherical bearings.

The smaller bushing is less noticeable but rubber, poly, and spherical options exist.

A lot to go through. For a tracking occasionally, mostly for fun car...replacing the rear links that give you some adjustability is a great start with minimal drawback besides cost. The driveline bushings, subframe inserts, and steering rack bushings make the car feel more confidence inspiring and connected, with slight increase in noise from the driveline bushings. The big front control arm bushing is an important one, but worth doing later as you assess your goals for the car.

- Andrew

[Racecomp Engineering]

Originally Posted by staples323

I'm moving closer and closer to going into NASA TT5 (HPDE 4 currently) and want to upgrade from the stock suspension before making the move to time trial.

CSG Mike posted this Questionnaire and figured I'd use it to make things easier

- What your experience level is: HPDE 4/ about 2 years track time with the BRZ and 3 years of kart racing before that
- What wheel sizes (size, offset) are on the car: 17x8 +42 TC105X
- What tires (type, size) are being used on the car: 225/45/17 Hankook RS4, may switch to similar-size Maxxis RC1 or Toyo RR in time trial
- What kind of car balance you are looking to achieve: Trying to keep the car similar balance to stock/ RCE swaybars currently, may go back to stock rear
- If there is Aero on the car: No aero/ may in the future
- If there is FI on the car: No FI
- If there are already supporting suspension mods on the car (bushings, arms, camber plates, etc.) Camber bolts. If future coilovers do not come with camber plates these will be added/ spl rear control arm is also planned.

Single or double adjustable/ no external reservoir, don't want to take the mod penalty in TT5. American or have U.S. factory support preferable for ease of rebuilds

$3-4k budget range

Thank you for any input you guys have.

Sorry I missed this! Did we talk via PM? Looking at your answers here...RCE Tarmac 2s make a lot of sense. No external reservoir, track focused, will work nicely with our swaybars, fit your budget and tire choice, etc.

- Andrew

[Ohio Enthusiast]

Originally Posted by Racecomp Engineering

The big front control arm bushing is an important one, but worth doing later as you assess your goals for the car.

Would you say this bushing is a good "feel mod" for a street daily driver? I've done all the other bushings you've talked about (except engine mounts), and really enjoy the solid driveline feel. I'm not really sure if I can feel a difference with the steering rack bushings (got poly bushings there), might be just a placebo effect. Would the big control arm bushings be on the same level as the steering rack bushings in terms of steering feel improvement?

[Racecomp Engineering]

Originally Posted by Ohio Enthusiast

Would you say this bushing is a good "feel mod" for a street daily driver? I've done all the other bushings you've talked about (except engine mounts), and really enjoy the solid driveline feel. I'm not really sure if I can feel a difference with the steering rack bushings (got poly bushings there), might be just a placebo effect. Would the big control arm bushings be on the same level as the steering rack bushings in terms of steering feel improvement?

The big front bushing is more than a feel mod...the OEM bushing is designed to deflect in certain ways. The firmer rubber of the group N bushing reduces this, and a spherical bearing will eliminate that entirely. So, sharper reactions due to the bushing not deflecting as much but also reduced changes in alignment under corner/braking. That can translate to more grip.

- Andrew

[staples323]

Originally Posted by Racecomp Engineering

Sorry I missed this! Did we talk via PM? Looking at your answers here...RCE Tarmac 2s make a lot of sense. No external reservoir, track focused, will work nicely with our swaybars, fit your budget and tire choice, etc.

- Andrew

Thanks for the reply RCE. We did not talk over pm, didn't even think about it

The Tarmac 2's are on my short list

[Racecomp Engineering]

Originally Posted by staples323

Thanks for the reply RCE. We did not talk over pm, didn't even think about it

The Tarmac 2's are on my short list

No worries! Let me know if you have any questions or give us a call (you'll reach Myles who has even more experience than me).

- Andrew

[cueball89]

Any recommendations on a camber gauge for DIY alignments?

[Plumbus]

Hey @CSG Mike @Racecomp Engineering,
Do any of you guys know what the upper knuckle hole in the RS-R rear lower control arm do? Is it used to correct roll center like the Whiteline roll center correction kit does with the front LCA, assuming you adjust coilover height to keep the same ride height?

[marco_mc22]

Originally Posted by Plumbus

Hey @CSG Mike @Racecomp Engineering,
Do any of you guys know what the upper knuckle hole in the RS-R rear lower control arm do? Is it used to correct roll center like the Whiteline roll center correction kit does with the front LCA, assuming you adjust coilover height to keep the same ride height?

The lower knuckle hole can be used to extend a bit the shocks, so more compression travel and less droop, nice for very low ride height since rear travel is limited even at stock height. The three holes for the shock point are used for obtaining three different motion ratio’s, usually about 0.5 difference per hole, this means if you put on the inner hole your shock, a wheel load for a 5kg/mm spring became 2.45kg/mm instead of 2.8kg/mm using the factory 0.75 motion ratio hole. This gives you the flexibility to fine tune your balance just swapping the shocks mounting positions, very useful
To raise your rear roll center you need to raise the upper control arm mounting position, maybe with the whiteline camber kit, then you could adjust camber with these lower arms.
Don’t know if the two holes for endlink point actually made some difference in leverage but probably yes, wait for other opinion