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

[CSG Mike]

Originally Posted by ayau

Mike said the rear toes out under compression. Which one is it?

What about the front?

Ooops did I? I need more coffee. It toes in under compression.

[solidONE]

Front end gets toe in under compression. Tho my toe has stayed pretty much at 0 even after lowering 1" and adding 1.5 degrees of negative camber using concentric bolts.

I have toe in after lowering 1" in the rear.

[Racecomp Engineering]

Originally Posted by ft_sjo

@Racecomp Engineering @CSG Mike


So I heard someone mention somewhere on this forum the other day about the 'British Approach' (or similar) on springs and anti-roll bars. The statement was around soft sprung damper/spring package and controlling balance with a/r bars.

This is the approach which I have been taught by my mentor (ex-WRC engineer). Our roads here are as you may suspect, very variable. The best roads in England tend to be quite challenging to suspension and overly-stiff tends to perform poorly. I consider the OE damper/spring package on the GT86 pretty good for our 'b roads' (country lanes). Car changes direction quickly, gives reasonable ride quality, not 'crashy' and gives a nice cushion for those rare times I get air.

My car has stock suspension apart from a 16mm rear bar. I found an 18mm bar upset the balance and made it less predictable. Front bar is stock as I don't consider the car has excessive roll. I'm also running AD08 tyres.


So i'm curious what your guys views would be on this style of chassis tuning, versus what I think is your preferred method of stiffer spring and less a/r bar (or even none).

Thanks.

British approach (sometimes australian approach thanks to the folks at Whiteline) is one way to do it and it can be pretty darn good. It has it's advantages as you said on rougher roads. We actually are fairly big proponents of this if budget is limited and/or it's a car that's driven on the street often.

Ideally for a racecar you rely more on springs and use bars as a trim device, but the world isn't always ideal.

- Andy

[Racecomp Engineering]

Originally Posted by meeks

what can i say? i am a sucker for good suspension porn. haha

in all seriousness, i would like to hear your opinions about mixing and matching springs on konis or the up and coming rce bilsteins.

the reason being is that i would like to see the front a little lower than the back without going the coilover route. i.e. rce gray springs in the front (tarmac? correct me if i am wrong) and rce yellows in the back (maybe a custom spring rate on that to retain balance and match the front spring rate the rce grays have).

budget wise, i do not know how much more or less it would cost (so please, put away your pitchforks and torches, it is a legit question) but i have yet to see somebody do custom spring swaps like a bunch of my friends that have ae86s that do a lot of auto-x/trackdays. they do mix and matches with springs on fixed after-market dampers and as far as i can see, they are pretty effective on that platform. competitive and effective, yet it achieves the look that i am aiming for.


this thread is like brazzers.com in full hd for suspension nuts. thanks again!

An ass up rake may not be a good idea for this car for handling. It depends on the rest of the set-up.

You can do custom spring combinations but not many vendors will sell half of a spring set.

- Andy

[Racecomp Engineering]

Originally Posted by supramkivtt2jz

2) does lowering the vehicle beyond 1 inch not alter the geometry with springs? I was under the impression ~0.5 inches lower was where the suspension was designed to operate. source:http://www.ft86club.com/forums/showp...5&postcount=11

Lowering or raising the car at all changes the geometry. It's just a question of how much.

I don't buy the 0.5 inches lower is where the suspension was designed to operate comment. It was designed to operate exactly the way it is. All we and every other aftermarket company is change things to hopefully improve on things that we want to improve. Whether it's looks, handling, ride quality, or some combination of those things.

You can change a lot on this car. I can make it so that it sits 2 inches lower and has better geometry than it would at stock height. Or lower it 0.5 inches and make it suck. Or anything really. There is NO one magic ride height where everything is perfect just because you are at the ride height. There's a full system with many variables to look at, deal with, and make compromises on. Sometimes the compromise pay off with quicker laptimes. Sometimes.

- Andy

[kanundrum]

Originally Posted by CSG Mike

Track:

Coilovers: CSG-Spec Tein SRC
LCAs: none
Other suspension components: none
Alignment:

Front
-3 camber
0 toe

Rear
-2.4 camber (natural from ride height drop of -1.4")
0 toe

Thanks! And @racecompengineering ?/

[Racecomp Engineering]

Originally Posted by mike the snake

I'm lowered 1.5" with ST coilovers (same as KW V1) and I'm looking at getting some aftermarket rear lower control arms.

Some, like the Stance ones, are shaped so they in effect raise the hub, and in reading about them, they say this is good for coilovers like the KW's which adjust height by spring preload.

So, I'm gathering the Stance LCA's offer more droop?

Are they a good match for my ST coilovers?

The Stance ones are interesting to me but I have not tried them. Off the top of my head for a given ride height you would get more bump travel and less droop travel. Overall a good thing.

- Andy

[Racecomp Engineering]

Originally Posted by BRZ NA

So what's the Max lowering ride height for tarmac 2 without effecting the original handling? or best ride height for tarmac 2 ?I want to lowered the car about 2"from stock height, is there anything I need to replace? thx

Just putting the T2s on affects original handling. That's the whole point!

We have found some of our best laptimes approx 1.5 inches lower than stock. You can go a little lower or higher. At that ride height I would recommend parts to be able adjust rear camber (either LCAs or the WL rear camber bushing).

- Andy

[BRZ NA]

Originally Posted by Racecomp Engineering

Just putting the T2s on affects original handling. That's the whole point!

We have found some of our best laptimes approx 1.5 inches lower than stock. You can go a little lower or higher. At that ride height I would recommend parts to be able adjust rear camber (either LCAs or the WL rear camber bushing).

- Andy

So my thought of specs should be ideal for track right?

[Racecomp Engineering]

Originally Posted by kanundrum

I am sure this will benefit everyone But list your Ideal Track Setup along with alignment specs using the following supplies. Then List your Ideal AutoX Setup if it differs.

Coil Overs: RCE 0 or Tarmac 2's (Along with KW V3 and Club Sport Equivalents)
LCAs: Choose your Flavor
Other Suspension Components to adjust geometry:
Alignment : Free Range List specs

My ideal track set-up....hmmmmm.....

Coilover: JRZ motorsports 4 ways (with JRZ Bryan Hise helping us with set-up)
LCAs: Don't care, something with quality pillowballs
Other components: replace all bushings with pillowballs. Front roll center adjustment. Lowering camber plates. Lowering rear top mounts.
Alignment: -3.5 degrees front, -2.2 degrees rear camber, or in that ball park depending on spring rates and tires. Toe to suit driver. Caster to suit track

That would be pretty nice. Pinch me.

RCE T2 clubsports would be the realistic choice but if we're dreaming....

Seriously, I really like our RCE T2 clubs. For the money it's hard to beat. Replace the JRZs with our stuff and you're still sitting pretty and your wife/husband/SO won't stab you because going out to dinner now means peanut butter jelly time.

- Andy

[Racecomp Engineering]

Originally Posted by BRZ NA

So my thought of specs should be ideal for track right?

In the right neighborhood but need to know tire choice.

- Andy

[Racecomp Engineering]

Originally Posted by solidONE

What about these guys?



The digressive valving looks pretty decent with really broad range of adjustment, though not quite sure how digressive rebound damping is beneficial to performance. I'm used to seeing just digressive comp damping in some premium grade dampers (penske ohlins). I think AST are going double digress ive with their new 4150 line as well. Fortune seems to offer different valving to match whatever spring rate you order. This is much better than a lot of other brands who only offer the same damping curves for different spring rates. Seems like the components they use to build their dampers are really good quality as well.

What do you guys think?

I would like to dyno them myself.

The compression adjuster doesn't seem to be doing much in the low-speed range and is basically just moving the knee. Big effects on mid and high speed. Yes you can feel that but there isn't a huge amount of benefit. Honestly they're only "digressive" in compression when they're cranked way up.

- Andy

[Racecomp Engineering]

I'm going out of town and almost completely off the grid for 7 days...CSG will have to hold it down in this thread!

- Andy

[BRZ NA]

Originally Posted by Racecomp Engineering

In the right neighborhood but need to know tire choice.

- Andy

Planning to go w hankook rs3, may be stock size first then 255/35/18 later