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

[8R6]

i just spent a couple hours re-reading this thread because i forgot a majority of the info the first time around... and now i cant remember what i read earlier. LOL.

I'm currently on hotchkis springs w/stock shocks and camber bolts up front. i love the way the car handles and feels and had fun, but now want to change things up and go a little lower. once i get adjustable coilovers, will i "need" adjustable toe arms for the rear if i'm lowering overall height about 1.75" from stock height? i plan on getting new rear LCA's to help dial in rear camber, but not sure if the adj toe arms are needed with a 1.75" drop. thanks in advance!

[cjd]

Originally Posted by BRGT86

will i "need" adjustable toe arms for the rear if i'm lowering overall height about 1.75" from stock height? i plan on getting new rear LCA's to help dial in rear camber, but not sure if the adj toe arms are needed with a 1.75" drop. thanks in advance!

Not usually. LCA is needed to have full control over camber but toe us usually within stock adjustability limits. Of everything is perfect you might even find camber is perfect and even without LCA's.

[Guillaume]

@CSG Mike, @Racecomp Engineering, I have an alignment question for you.

I just had Öhlins Road & Track coilovers installed and after some mileage to let everything settle in, it is time for a proper alignment.

Use: I use the car as a daily driver but I do track it quite a bit too. 8 to 10 track events per year and lots of spirited driving. I'd say I am a reasonably experienced driver.

Set-up:

• Daily tires are Michelin PS3s (215/45/17)
• Track tires are Yoko AD08Rs (225/45/17)
• 10 mm drop with the coilovers
• No other suspension mod (no LCA, no adjustable bushing of any sort)

I was planning on asking the following alignment:

Front:

• Camber: -1.5°
• Caster: no clue (is it even adjustable?)
• Toe: 0 (total toe: 0 too?)

Rear:

• Camber: -1.3° (as is right now with the 10mm drop)
• Toe: 0 (total toe: 0 too?)

Does that seem sensible? I don't wanna kill my tires too fast on the road, I like a reasonably tail-happy car. Should I go for more negative camber at the front? I think Öhlins' camber plates can give up to -3° or so.

Thanks!

[Racecomp Engineering]

Originally Posted by Guillaume

@CSG Mike, @Racecomp Engineering, I have an alignment question for you.

I just had Öhlins Road & Track coilovers installed and after some mileage to let everything settle in, it is time for a proper alignment.

Use: I use the car as a daily driver but I do track it quite a bit too. 8 to 10 track events per year and lots of spirited driving. I'd say I am a reasonably experienced driver.

Set-up:

• Daily tires are Michelin PS3s (215/45/17)
• Track tires are Yoko AD08Rs (225/45/17)
• 10 mm drop with the coilovers
• No other suspension mod (no LCA, no adjustable bushing of any sort)

I was planning on asking the following alignment:

Front:

• Camber: -1.5°
• Caster: no clue (is it even adjustable?)
• Toe: 0 (total toe: 0 too?)

Rear:

• Camber: -1.3° (as is right now with the 10mm drop)
• Toe: 0 (total toe: 0 too?)

Does that seem sensible? I don't wanna kill my tires too fast on the road, I like a reasonably tail-happy car. Should I go for more negative camber at the front? I think Öhlins' camber plates can give up to -3° or so.

Thanks!

I would go for more negative camber all around. With 0 toe you could run -2 front without much worry on uneven wear. Even a little more would suit you well. I would run -2.5 front and -1.8 rear. Caster is non-adjustable.

- Andy

[dp1]

I have Ohlins R&T, now revalved with 380f/420r spring rates, and similar use pattern. Many other mods. My favorite alignment for track was -3.4f/-2.7r with max caster (push camber plates towards back of the car before tightening three bolts) and zero toe. Drove car daily on the street with this setup on PSS and without excessive tire wear on inside edges, loved it on track with Toyo RA1. I don't care about 0-60 and never drop clutch. I believe that outside edges will wear faster on track with less than -2 camber. I change camber to -1.5 and switch to winter tires Nov-Apr (North East).

[Racecomp Engineering]

Yes, with more camber you will be happier at the track and tire wear won't be bad with 0 toe.

- Andy

[OkieSnuffBox]

@CSG Mike, @Racecomp Engineering

Use: Daily driver that will see Auto-X and the occasional track day. Previous track toys include an R6 and a Miata with ASTs/Wilwoods/etc.


Setup:
- Ground Control coilovers 375/425
- Stock sways


Currently on the stock tires, I just maxed the camber in front and whatever camber I have in the rear. Car is lowered just over 1". The car is incredibly tail happy with these rates (bought them used) and if I forget to turn off TC, it engages all the time when I don't even have any slip angle. I suspect these rates are seriously overwhelming the stock tires.


Will be installing SPL lower control arms and 18x9.5 w/255/35 Direzza ZII's on the car and getting an alignment in the next 1-2 weeks.


Thinking something like:


Front:
-2.5-3.0, 0 toe


Rear:
.5 less camber than front, just a tad toe-in.


Thoughts?

[Racecomp Engineering]

Originally Posted by OkieSnuffBox

@CSG Mike, @Racecomp Engineering

Use: Daily driver that will see Auto-X and the occasional track day. Previous track toys include an R6 and a Miata with ASTs/Wilwoods/etc.


Setup:
- Ground Control coilovers 375/425
- Stock sways


Currently on the stock tires, I just maxed the camber in front and whatever camber I have in the rear. Car is lowered just over 1". The car is incredibly tail happy with these rates (bought them used) and if I forget to turn off TC, it engages all the time when I don't even have any slip angle. I suspect these rates are seriously overwhelming the stock tires.


Will be installing SPL lower control arms and 18x9.5 w/255/35 Direzza ZII's on the car and getting an alignment in the next 1-2 weeks.


Thinking something like:


Front:
-2.5-3.0, 0 toe


Rear:
.5 less camber than front, just a tad toe-in.


Thoughts?

Yeah those rates are too high for the stock tires but should be fine with the ZIIs. Might still be tail happy though.

Alignment sounds good.

- Andy

[PandaBRZ]

Hey, guys.

I recently switched from stock wheels and tires to 17x8 wheels and 225/45/17 MPSS. What I noticed is that the traction control light is coming on a lot more on the same canyon roads I used to drive. The weird thing is that I don't feel the car being loose at all. There's no tire squeal and no opposite lock needed to correct when the traction control light flashes.

I got an updated alignment when I got the wheels and tires mounted too. Could the new alignment settings be to blame? Here's the alignment sheet:

[Kostamojen]

Ok, I'm wrestling with some theoretical ideas here...

After switching tire sizes (from extremely heavy 18's with 245/45/17's to 16's with 225/45/16's) strictly for performance reasons, I'm extremely happy with the outcome. Grip is still there, maybe even more so, because of the quality of the tire (ZII Star Specs) and the shorter tire combined with the VERY light weight wheel/tire combo has improved gearing/acceleration dramatically.

However, with the suspension mods I was running previously with the larger wheels (RCE springs, Strano FSB, Perrin adjustable RSB, camber bolts... front strut bar, thats about it) the larger rear swaybar in the rear was causing snap oversteer with the new setup. I believe it caused the rear tire to left and therefore issues with the Torsen diff which caused the snap oversteer especially when throwing the car around.

So today I removed the swaybar for the stock bar, and now the car is MUCH better at holding power in a corner and much more controllable without the fear of snap oversteer. But the car does understeer a bit more now and I'm not sure how well it will hold up in Autox (Daily driver/Autox setup, not for track days).

I believe I need to do something with the rear shocks/springs to compensate for this...

Right now, I am very happy with the RCE springs and how they work with the stock shocks, and the fact they only lower the car slightly which doesn't compromise suspension geometry but you still get the benefit of the stiffer rates and lower COG.

I've mentioned this before, but I was really happy with using BRZ front springs and FRS rear springs in conjunction with the Strano FSB and camber bolts for use in C-stock. My goal is to try and take that setup to the next level.

What I'm thinking is will a stiffer rear spring (lets say, a Tarmac rear spring, combined with a Yellow front spring) allow the torsen diff to stay active yet let the car have less understeer during corner entry and a better "slip angle" I guess is the term, for during a steady state corner?

Plus, combining that stiffer rear spring with an adjustable shock like the Cusco shocks, might allow it to get to just right while avoiding changing the rear sway bar?

I have no interest in coilovers, I don't need an adjustable height nor more clearance for larger tires. Plus the ability to run Group-N top hats is something that appeals to me greatly, I've used those before on my Impreza and they work so damn well.

For reference, I have run adjustable shocks before (AGX's, twice, one with adjustable Ground Control springs the other with the famous SPT springs) and coilovers on my Impreza. I also replaced literally every bushing on that car, so I'm quite familiar suspension wise with anything Subaru.

So what do you guys think?

[Kostamojen]

No comment???

[Racecomp Engineering]

Originally Posted by Kostamojen

Ok, I'm wrestling with some theoretical ideas here...

After switching tire sizes (from extremely heavy 18's with 245/45/17's to 16's with 225/45/16's) strictly for performance reasons, I'm extremely happy with the outcome. Grip is still there, maybe even more so, because of the quality of the tire (ZII Star Specs) and the shorter tire combined with the VERY light weight wheel/tire combo has improved gearing/acceleration dramatically.

However, with the suspension mods I was running previously with the larger wheels (RCE springs, Strano FSB, Perrin adjustable RSB, camber bolts... front strut bar, thats about it) the larger rear swaybar in the rear was causing snap oversteer with the new setup. I believe it caused the rear tire to left and therefore issues with the Torsen diff which caused the snap oversteer especially when throwing the car around.

So today I removed the swaybar for the stock bar, and now the car is MUCH better at holding power in a corner and much more controllable without the fear of snap oversteer. But the car does understeer a bit more now and I'm not sure how well it will hold up in Autox (Daily driver/Autox setup, not for track days).

I believe I need to do something with the rear shocks/springs to compensate for this...

Right now, I am very happy with the RCE springs and how they work with the stock shocks, and the fact they only lower the car slightly which doesn't compromise suspension geometry but you still get the benefit of the stiffer rates and lower COG.

I've mentioned this before, but I was really happy with using BRZ front springs and FRS rear springs in conjunction with the Strano FSB and camber bolts for use in C-stock. My goal is to try and take that setup to the next level.

What I'm thinking is will a stiffer rear spring (lets say, a Tarmac rear spring, combined with a Yellow front spring) allow the torsen diff to stay active yet let the car have less understeer during corner entry and a better "slip angle" I guess is the term, for during a steady state corner?

Plus, combining that stiffer rear spring with an adjustable shock like the Cusco shocks, might allow it to get to just right while avoiding changing the rear sway bar?

I have no interest in coilovers, I don't need an adjustable height nor more clearance for larger tires. Plus the ability to run Group-N top hats is something that appeals to me greatly, I've used those before on my Impreza and they work so damn well.

For reference, I have run adjustable shocks before (AGX's, twice, one with adjustable Ground Control springs the other with the famous SPT springs) and coilovers on my Impreza. I also replaced literally every bushing on that car, so I'm quite familiar suspension wise with anything Subaru.

So what do you guys think?

What's your alignment like? How big was the Perrin rear bar and where was it set?

- Andy

[Kostamojen]

Originally Posted by Racecomp Engineering

What's your alignment like? How big was the Perrin rear bar and where was it set?

- Andy

Alignment is (negative camber) ~1.5 front, ~1.0 rear. Zero toe all around.

19mm set to minimum stiffness

[Racecomp Engineering]

Originally Posted by Kostamojen

Alignment is (negative camber) ~1.5 front, ~1.0 rear. Zero toe all around.

19mm set to minimum stiffness

19mm is pretty darn big. FWIW our RCE rear swaybar is a 19mm hollow, which works out to a 16mm solid. I don't like going bigger than that for most applications.

With just the front bar, yes you will have some hard to tune out understeer. You could with a 16mm adjustable or try the 16mm Subaru bar for cheap. That should balance things out nicely.

- Andy