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

[Racecomp Engineering]

Originally Posted by OND

Do you have the stock spring dyno charts with bumpstops? I am wondering how much progressiveness they add and at what point of travel they start working.

Ahhh I have to dig, but these cars are very bumpstop active. Part of why I don't jump into the debate on the OEM spring rates....once loaded up in basically any corner you're on the bumpstops. FRS just "bites" a little better until you're on the bumpstops.

- andrew

[OND]

Originally Posted by Racecomp Engineering

Ahhh I have to dig, but these cars are very bumpstop active. Part of why I don't jump into the debate on the OEM spring rates....once loaded up in basically any corner you're on the bumpstops. FRS just "bites" a little better until you're on the bumpstops.

- andrew

Thanks for the feedback!

I think that graph would be awesome for people like me who are on the fence about getting the RCE yellows, because I am pretty happy with the stock handling characteristics and just comparing the spring rates makes it look like yellows would change the balance of the car more than I'd like them to.

[Ro_Ja]

I have a general question about rear camber and its role and relative importance in the overall suspension dynamics and geometry of the car.

I understand adjustable control arms are great for setting specific alignment settings, but how important is that?

The Griffon, Gazoo, and TMG cars either have stock or TRD/STi links (probably mostly due to rules), and those cars have the crap driven out of them and it seems they're doing quite well without the adjustability.

I currently have Cusco LCAs, but I'm entertaining the thought of buying the STi link set (RLCA, toe links, and trailing arms) and I'm curious if there's a greater net benefit from making that switch and living without the adjustability. Thoughts?

[nikitopo]

Suspension geometry is just fine if you don't go lower than 1''. Main change in the STI kit is the replacement of the rubber bush part with a pillow ball on the trailing kit and lateral link set. They are saying that the rear suspension exhibits more linear characteristics and it is more controllable during a slide.

[Captain Snooze]

Originally Posted by SorryTires

For adjustable I was thinking Tarmac 2/KW V3, keep in mind I have zero experience setting up adjustable dampers but like the idea of learning.

Do it! I had zero experience too until I bought some 2-ways. Unlike Ebay specials with 40 click adjustments on quality dampers the individual clicks actually make a difference. It took me about a month of adjusting to get the set-up the way I liked then didn't touch them again. The main thing is to only make one adjustment at a time at one end. Having said that 2 click steps are good because they give a significant change then one can fine tune with 1 click adjustment.

[churchx]

Captain Snooze: but how about if one cannot go to track frequent enough / doesn't drive good & consistent enough, to evaluate adjustment changes or if those come in too small steps? I'd rather have one setup and then get used to it/adjust my driving to it, then doing lot of tries to get things better, when i wouldn't be able to tell if it's really improvement, or i simply made less mistakes during last laps .

[Captain Snooze]

Originally Posted by churchx

Captain Snooze: but how about if one cannot go to track frequent enough / doesn't drive good & consistent enough, to evaluate adjustment changes or if those come in too small steps? I'd rather have one setup and then get used to it/adjust my driving to it, then doing lot of tries to get things better, when i wouldn't be able to tell if it's really improvement, or i simply made less mistakes during last laps .

Thank you for your question. I understand what you are saying. It is a valid point.
But......and pardon me, I have given this spiel before. For me suspension is more......value than power. That is, the suspension is working at all speeds greater than zero. I am partially aware of what the chassis is doing most of the time regardless of speed. So even if one can not utilise all the benefit of 2 way dampers (I raise my hand here) one still gets the enjoyment/satisfaction/pleasure of quality damping.

Part 2. (And this has just occurred to me.) I am suggesting there are 2 aspects to the car. Firstly, objective performance (by making 2 clicks adjustment to the front the car is now 0.2 seconds quicker per lap. Secondly, steering behavior/car feel. (By turning 2 clicks at the front the front feels more planted)
The first point is totally beyond me; my lap times are, mmmmmm.... how can I say this without crushing my fragile ego..... let's say.... ah.....variable. The performance gains are not measurable, are immaterial (*sigh*) but the way the car feels/behaves is not measurable but is (maybe more) important to me.

[nikitopo]

Even if someone doesn't track an adjustable suspension can provide many benefits, like adapt it to particular tires or roads. Personally, I would like to try some new type of tires and I cannot do it because I know that the stock suspension will be a limiting factor. Same for different types of roads and quality of pavements where the stock car goes as shit. An aftermarket fixed setup might be a bit better and offer quality damping, but again it'll be a compromise on everything. So it is more than get used to it or adjust the driving. My only worry on 2 way (or even 3 way) adjustable suspensions is that they offer too much adjustability for the ordinary driver. I prefer the 1 way adjustables, since a suspension specialist has predefined how the compression & rebound values should match. More adjustments offer more flexibility, but require also very detailed knowledge and more time for changing the settings.

[Captain Snooze]

Originally Posted by nikitopo

My only worry on 2 way (or even 3 way) adjustable suspensions is that they offer too much adjustability for the ordinary driver........... More adjustments offer more flexibility, but require also very detailed knowledge and more time for changing the settings.

I think I qualify as, if not an ordinary ordinary driver then an intermediate ordinary driver . Seriously..... adjustment takes time but there is nothing difficult about the process. Make an adjustment. Do you like the change or not? Rinse, repeat.

3 ways are a different matter.

[Racecomp Engineering]

Originally Posted by Ro_Ja

I have a general question about rear camber and its role and relative importance in the overall suspension dynamics and geometry of the car.

I understand adjustable control arms are great for setting specific alignment settings, but how important is that?

The Griffon, Gazoo, and TMG cars either have stock or TRD/STi links (probably mostly due to rules), and those cars have the crap driven out of them and it seems they're doing quite well without the adjustability.

I currently have Cusco LCAs, but I'm entertaining the thought of buying the STi link set (RLCA, toe links, and trailing arms) and I'm curious if there's a greater net benefit from making that switch and living without the adjustability. Thoughts?

If you already have Cusco LCAs, you don't have anything to gain by switching to the STI LCA. We had the full STI rear end set and it was awesome, but we eventually swapped out the LCAs to Cuscos to get some adjustability.

Stock or lowered slightly you're in the right ball park for rear camber, but I'm pretty particular about alignments and we really wanted everything to be perfect.

- Andrew

[Racecomp Engineering]

Originally Posted by Captain Snooze

I think I qualify as, if not an ordinary ordinary driver then an intermediate ordinary driver . Seriously..... adjustment takes time but there is nothing difficult about the process. Make an adjustment. Do you like the change or not? Rinse, repeat.

3 ways are a different matter.

It takes a little time to get your head around separate compression and rebound adjustments, but if you're willing to make the effort they can be really valuable. A lot more so on a track or auto-x car that may see frequent changes to set ups, tires, and environments, but "nice" on a street car. I'm usually happy with a non-adjustable damper for the street, but it has to be really good from the get go (which is possible).

Take notes!

3 ways are definitely a little more involved. Fun, if you're a nerd like me.

- Andrew

[Gforce]

Originally Posted by Racecomp Engineering

Ahhh I have to dig, but these cars are very bumpstop active. Part of why I don't jump into the debate on the OEM spring rates....once loaded up in basically any corner you're on the bumpstops. FRS just "bites" a little better until you're on the bumpstops.

- andrew

Somewhere on here the travel distance before the bump stop engages was said to be about 1/2 in. TRD (Eibach ) lowering springs come with shorter bump stops, presumably for this reason. At least one lowering spring or coilovers instruction sheet requires the installer to cut what looks like one full section off the softest end of the stock bump stops.

It is possible to cut or drill factory bump stops to reduce the effective spring rate rise they cause as they engage. Bump stops are cheap and expendable. To preserve the factory engagement ring moulded into the top section one can: cut a slice out of the top section and glue it back together with goop or similar, cut off the softest section from the bottom (Eibach short bump stops appear to be moulded without this section) or drill a number of holes in any of the sections to soften the effective rate, logically one would drill out material from the smallest section first.

There is no question these cars ride the bump stops very early into the corners. Any suspension modification needs to take this into account, especially lowering.

[Gforce]

Originally Posted by Ro_Ja

I have a general question about rear camber and its role and relative importance in the overall suspension dynamics and geometry of the car.

I understand adjustable control arms are great for setting specific alignment settings, but how important is that?

The Griffon, Gazoo, and TMG cars either have stock or TRD/STi links (probably mostly due to rules), and those cars have the crap driven out of them and it seems they're doing quite well without the adjustability.

I currently have Cusco LCAs, but I'm entertaining the thought of buying the STi link set (RLCA, toe links, and trailing arms) and I'm curious if there's a greater net benefit from making that switch and living without the adjustability. Thoughts?

You're looking for adjustment capability if the rear contact patch is not flat on the road at the limits of suspension roll. On the street you are looking for that setting giving the flat contact patch for "most of your driving" or you will be wearing out your tires prematurely. Stock rear camber is generally adequate, especially if you lower your suspension by no more then one inch. Adjustability is useful also because the factory install is pretty sloppy and adjustment gives you the debility to equalize left to right camber without messing around trying to align the rear subframe more accurately.

Crash bolts give you around 0.5 degree additional camber range in the LCA inner bolt location. This is the easiest way to address minor camber changes. Add crash bolts to the front struts and you should be happy enough.

[n0thing]

Ap sprint kit here, have been using the ds2500 pads and they are due for replacement soon. The rotors have absolutely no cracks on them, but have a few ridges from the begining and end of the j hooks. I suppose this is common as the j hooks dig into the pads? I believe the rotors still have life in them, do I still bed in the new pads in the normal fashion? Will this damage the new pads? Thanks