RCE Tarmac 2 - Range of Ajdustment

[Kuro86]

I am in the new market for new shocks and the RCE Tarmac 2s have caught my eye. I was wondering if anyone knew how many clicks of adjustment there is for rebound and compression?

[redlined600]

Whether it's 5 or 50 is irrelevant, what matters is the actual change in damping.

http://www.ft86club.com/forums/showthread.php?t=71136

[strat61caster]

+1 Number of 'clicks' is not as important as the consistency and repeatability of any adjustments you make.

I'd rather have a well dialed in non-adjustable than a "XX way adjustable" mystery shock any day.

RCE & KW (the actual builder of the dampers) have good reputations, depending on what you're looking for odds are that they'll deliver.

[smg1138]

I have the T2's and the answer is it varies between compression and rebound. As memory serves, I get about 18 clicks rebound and a couple of clicks fewer compression. That being said, each click on these coilovers gives a significant and noticeable change in damping. Some cheaper coilovers might offer 30+ clicks but offer very little actual adjustability. If you're interested in a coilover for autocross or track days, you can't go wrong with the RCE T2's.

[Kuro86]

Originally Posted by redlined600

Whether it's 5 or 50 is irrelevant, what matters is the actual change in damping.

http://www.ft86club.com/forums/showthread.php?t=71136

The reason I ask is because Click 0 to 9 on the shock dyno show little change, but full stiff is a huge change.

So I'm wondering if the adjustments are not linear or if there are a ton of clicks.

[Kuro86]

Originally Posted by smg1138

I have the T2's and the answer is it varies between compression and rebound. As memory serves, I get about 18 clicks rebound and a couple of clicks fewer compression. That being said, each click on these coilovers gives a significant and noticeable change in damping. Some cheaper coilovers might offer 30+ clicks but offer very little actual adjustability. If you're interested in a coilover for autocross or track days, you can't go wrong with the RCE T2's.

Thank you for the feedback! I understand more clicks don't mean better. I'm just trying to understand the shock dyno better.

[MeisterR]

Most damping adjustment are not linear, because most adjuster is control via a bleed valve.

If you imagine a garden hose:
If you open the tap a quarter turn when it is fully closed, you get a lot of water coming out
If the tap is already half open and you open another quarter turn, the change won't be as great.
It is the same with the adjuster, a "click" on the stiffer end makes a much bigger difference then a "click" in the softer end normally.

This is why sometime suspension have a lot of clicks.
Because if you want to cover your range from full stiff to full soft, but still have control of the stiffer end, then you need to have fine adjustment and lots of them.

Example, let say you have 30 clicks that that move the valve 0.1mm per click.
If you want want to half it to 15 clicks, you have one of two choices.

1. change the pitch to 0.2mm, so you cover the same range in 15 clicks.
But you lose the "fine" adjustment you need at the stiff end.

2. change the range so you only have 15 clicks adjustment at 0.1mm pitch.
But you lose the soft end of the adjustment and that could mean even the softest setting still ride too harsh.

When it comes to damping adjustment, you want to make sure that you have the range as well as the fine adjustment you need.
The second thing is to make sure that you have the right damping force.
I see some damper that are WAY over dampened, and that mean on full stiff the damper stop the suspension from moving in it's natural frequency and can lead to all kind of poor vehicle dynamics that you just do not want in a car.

Hope that helps.

Jerrick

[redlined600]

Originally Posted by Kuro86

The reason I ask is because Click 0 to 9 on the shock dyno show little change, but full stiff is a huge change.

So I'm wondering if the adjustments are not linear or if there are a ton of clicks.

Gotcha, as stated above there likely is non linearity between adjustments.

[jamal]

It would be nice to see a sweep of more settings, but the big thing I take from the T2 plots is how the adjustments are mostly changing low-speed, and how much low speed compression they can generate, and how the forces don't get out of control at higher speeds. All good things IMO. If you have to turn the shocks way up to get good low speed force, or just plain never develop very much, I don't like that. And on a lot of low end stuff high speed rebound goes through the roof, especially on the stiffer settings.

disclaimer: I don't know as much about this as I would like, but when you look at plots from nice stuff they tend to agree with what I'm saying.

[Kuro86]

Originally Posted by MeisterR

Most damping adjustment are not linear, because most adjuster is control via a bleed valve.

If you imagine a garden hose:
If you open the tap a quarter turn when it is fully closed, you get a lot of water coming out
If the tap is already half open and you open another quarter turn, the change won't be as great.
It is the same with the adjuster, a "click" on the stiffer end makes a much bigger difference then a "click" in the softer end normally.

This is why sometime suspension have a lot of clicks.
Because if you want to cover your range from full stiff to full soft, but still have control of the stiffer end, then you need to have fine adjustment and lots of them.

Example, let say you have 30 clicks that that move the valve 0.1mm per click.
If you want want to half it to 15 clicks, you have one of two choices.

1. change the pitch to 0.2mm, so you cover the same range in 15 clicks.
But you lose the "fine" adjustment you need at the stiff end.

2. change the range so you only have 15 clicks adjustment at 0.1mm pitch.
But you lose the soft end of the adjustment and that could mean even the softest setting still ride too harsh.

When it comes to damping adjustment, you want to make sure that you have the range as well as the fine adjustment you need.
The second thing is to make sure that you have the right damping force.
I see some damper that are WAY over dampened, and that mean on full stiff the damper stop the suspension from moving in it's natural frequency and can lead to all kind of poor vehicle dynamics that you just do not want in a car.

Hope that helps.

Jerrick

This does help! Thank you for the response.

[renfield90]

As a T2 owner who has dyno'd their shocks:

- You are guaranteed 16 clicks each of rebound and compression. I think on rebound I have a few more clicks than that (but you likely don't need to be softer than 16 anyway)
- There is no crosstalk between the two adjusters; changes to rebound do not affect compression and vice versa (this is good, and actually tricky to engineer)
- There is some non-linearity at the full hard end of the adjusters (last click), this is to be expected with almost any shock (keep making the straw smaller and at some point a small change has a big impact). The rest of the range is very linear (this is good)
- The size of the adjustment is pretty good. For coarse tuning I will make adjustments two clicks at a time, for fine tuning I'll go one click at a time
- The left/right shocks matched each other perfectly on the dyno (many budget shocks fail even this most basic test)

Can't go wrong with these.

[Racecomp Engineering]

Thanks @renfield90 !

Here's a shock dyno for our T2 Clubsports for BRZ (fronts).



It's the one I have on hand right now, which means it's the pretty one from our fact sheet. We're in the process of uploading better shock dynos for all of our coilovers to the website.

One thing we focus on with our T2s is the digressive compression damping. You can get plenty of low speed damping without an excessively high damping ratio for high piston speeds. And the "middle" settings are useful and make noticeable differences to both high and low piston velocities. Sometimes you'll see a shock dyno and the adjuster makes a big difference for high piston speeds but not much of a difference below 2 inches per second (body roll). So you're actually not tuning handling as much as you think.

- Andrew

[StraightOuttaCanadaEh]

Okay so for the rebound adjustments, is a full turn with the 2 mm allen considered one click? I did almost a full turn and don't hear or feel any clicking

[cmiovino]

Originally Posted by StraightOuttaCanadaEh

Okay so for the rebound adjustments, is a full turn with the 2 mm allen considered one click? I did almost a full turn and don't hear or feel any clicking

If they're similar to the SS-1 and SS-2, they don't audibly "click". They do have some notch feeling when it's in the next setting, but I know one of mine in the rear is kinda vague.

It's best to put them to full soft so you know where that is. Then you can move the adjuster over one "click" by seeing the number (on the KW 2mm adjuster) move to the next position.

I can see how it can be kinda tricky to see what position or click you're in using a 2mm allen alone. Spend the $25 on the adjuster if you don't have one.