Review: 3DM Öhlins R&T kit + TMS camber plates + Syncro Design Works tension arms

[IamFODI]

Well, I decided to make the switch to the Ohlins....install next week!

Curious, how many clicks are you running the dampers, front and rear?

Nice. Interested to read your impressions.

I ended up 5 clicks from the firmest setting all around. Based on forum posts, other people have chosen very different settings, so I'd strongly recommend trying things yourself. IMO the most important thing about the setting is how you arrive at it. Here's the procedure I posted in another thread:

Start at the softest setting and drive around. Pay attention for whether the car flops around or bounces more than you'd like. If it does, dial the damping up one click. Repeat until you find the setting you like.

At some point, you might realize that increasing damping doesn't make the car feel better. If that happens, come back down to the softest setting before things stopped improving. E.g., if anything past 6 doesn't help, keep it at 6. I pulled that number out of thin air but you get the point.

Ideally, this should be done one axle at a time. I.e. see whether the front or rear is the source of the excess motion and tweak only that axle -- or try each individually before clicking all of them up. The former requires you to be a lot more sensitive and perceptive; the latter takes a lot more time. If you don't want to mess with that, just raise all the settings together.

This applies to any adjustable damper. Other people's preferred settings can be good sanity checks -- e.g. if everyone says 5 and you hate anything besides 10, it might make sense to revisit your perceptions (again, totally made those numbers up but you get the point). However, the reality is that you'll have to do some tweaking no matter what, so IMO you might as well start from scratch.

The reason for starting at full soft is that you want only as much damping as you need, and no more. As much as necessary, but as little as possible.

[ultimatemj]

Well, I decided to make the switch to the Ohlins....install next week!

Curious, how many clicks are you running the dampers, front and rear?

[IamFODI]

The only road imperfections I avoid are the absolute biggest bumps/potholes (bump stop hits are extra loud with this setup). Everything else is a non-issue for me. It doesn't have the eerie smoothness and composure of a modern sport/luxury car, but it's good enough that I can just drive and not worry about the condition of the pavement.

This comment hasn't aged well.

The roads around where I live have been horrendous this winter. Worse than normal. Big dips and heaves, major potholes, and some very broken pavement everywhere. That means a really busy ride, lots of impact noises, and frequent worries about running out of bump travel.

Not that the stock setup was much fun on roads like this, either. But at least it didn't constantly threaten a huge "BANG" where most cars would only make a mildly disconcerting "thump."

So I guess, if your roads are in a state of hideous state of neglect, don't buy travel-limited coilovers or replace all the rubber in your front suspension with sphericals. 😛

[IamFODI]

I don't see/recall your tire setup, but Dinan has some info in their suspension kit about how front/rear tire size difference influences turn in...might be something to consider

245f/265r PS4S. Definitely thinking about other setups for whenever I'm ready for dedicated track tires.

Saw some chunking on the outer edges of the front tire on my most recent track days, so it seems advisable to run more camber at the track. I'm sure that'll help some.

Street use is a tougher nut to crack. Don't want wider tires because I don't want to reduce hydroplaning resistance (already unhappy on this point -- my last car was better). Don't want more camber for wear reasons. But understeer is much less of a problem on the street anyway, for obvious reasons.

How's the ride quality "around town"? Do you find yourself driving around road imperfections, or does the set up do fine around town?

Overall, I feel about the same now as I did when I wrote my initial impressions of ride quality.

The only road imperfections I avoid are the absolute biggest bumps/potholes (bump stop hits are extra loud with this setup). Everything else is a non-issue for me. It doesn't have the eerie smoothness and composure of a modern sport/luxury car, but it's good enough that I can just drive and not worry about the condition of the pavement.

[ultimatemj]

This is definitely a very understeer-biased setup. I'd love a bunch more front end grip and pointier steering response. But I understand I can't do much to get that without massively lightweighting the car or sacrificing some limit friendliness

I don't see/recall your tire setup, but Dinan has some info in their suspension kit about how front/rear tire size difference influences turn in...might be something to consider

INSR190-9131Page 14of 16Rev. 4not turn well when going fast.If you drive the car fast,you will punish the front tires so much that they will overheat the compound and actually increase under-steer as the tires get older.
30mm smaller front tires:If you have 30mm smaller front tires than the rear,you will have noticeable under-steer, probably more than desired. This is the typical factory M-car set up, designed to make enough under-steer to keep you out of trouble. If you drive the car fast, you will punish the front tires a little more than the rear, which will overheat the compound and actually increase under-steer slightly as the tires get older. This is the safest combination.
20mm smaller front tires:If you have 20mm smaller front tires than the rear, you can achieve a well balanced car. This is the typical Dinan configuration, designed to make it possible to achieve under-steer or over-steer at will, based on your set up and driving style. If you drive the car fast, you will punish the tires equally, so the car will remain balanced as the tires get older.
10mm smaller front tires:If you have 10mm smaller front tires than the rear,you can achieve a well balanced car. This will make it possible to achieve under-steer or over-steer at will based on your set up and driving style. If you drive the car fast,you will punish the rear tires slightly more than the fronts, and the car will develop a slight over-steer as the tires gets older. This is only true of a high powered car because of its ability to “turn the rear tires over”. A low-powered car will maintain good balance,and the rear tires will not degrade more quickly than the fronts.
Equal sized tires front & rear:If you have equal sized tires front and rear, you can achieve a well balanced car. This will make it possible to attain under-steer or over-steer at will, based on your set up and driving style. You will punish the rear tires a lot more than the fronts, and the car will develop a significant over-steer as the tires get older. This is more true of a high powered car because of the ability to “turn the rear tires over”. It’s OK to install a smaller rear tire to balance the car. Oftentimes people put on a larger rear tire, when a smaller one will actually make the car handle better.

How's the ride quality "around town"? Do you find yourself driving around road imperfections, or does the set up do fine around town?

Thanks

[IamFODI]

Time for some track impressions. 7 trackdays on this setup, all at NJMP (5 at Thunderbolt, 2 at Lightning). Street tires and brakes, zero power mods, novice-to-intermediate pace.

BLUF: Couldn't have asked for anything better.

You can really tell Öhlins developed the basic R&T kit at a track. Everything about its behavior is well controlled. I made my share of mistakes but the car never put a foot wrong.

It rides curbs like an absolute champ. The suspension shrugs off the initial impact, eats up the rumble strips if you hit them, and lets you back on the pavement with zero drama.

Handling is very intuitive and noob-friendly. Understeer is predictable. Oversteer is super progressive. Either condition is eminently correctable. Enough bark, zero bite.

This is definitely a very understeer-biased setup. I'd love a bunch more front end grip and pointier steering response. But I understand I can't do much to get that without massively lightweighting the car or sacrificing some limit friendliness, so I'm not unhappy on this front.

Overall, I would strongly recommend this setup for someone in my shoes (track noob who DDs the car).

[IamFODI]

Curious what happened next...

At some point after the post you're responding to, I decided to lower the front just a smidge to ZCP height (rear was already there) and, while I was already messing with it, took the opportunity to trade some droop for 4-5 mm more bump up front. If that made a difference at all, it was minor.

I also sustained a few more bump stop hits on awful roads (not sure there's any other kind around here any more) and noticed zero ill effects other than the obvious unpleasantness. It's alarmingly loud when it happens, which in retrospect was probably my whole reason for wanting to change suspension settings to mitigate it. But then I realized my monoball camber plates and FTABs were probably making those hits sound much worse. Maybe I was overestimating how bad the impacts really were for the car.

Lastly, I'm not sure it's possible to achieve a bunch more bump travel without sacrificing too much droop. It seems like the only real way to solve the problem is with significantly longer damper bodies, which would basically require re-engineering the kit -- something I was trying to avoid in the first place.

On balance, if the only issue is very rare and brief moments of unpleasantness -- a lot of which will go away once the roads are finally re-paved -- that doesn't feel to me like enough reason on its own to dig further into this when I can't be fairly sure that the end result will be better overall.

I'm unhappy with my ride quality and my gut is the front is oversprung (8k(448lbin) which is mild by some but my understanding is stock ZCP is 3k(167lbin)...but my issue could just as easily be improper pre-load, so I've got some investigation to do.

Moved my response and subsequent discussion to a new thread.

[Obioban]

Plan for the future: more bump travel.

Reasons:

1. Just hit the bump stops for the 3rd time since the install today. Horrible bumps -- far from the norm -- but if I can solve it, why not?
2. Calculations suggest I don't have much bump travel right now, and a ton of room to trade droop travel for it

I haven't taken any measurements; just calculated. Given:

- 343 lbs/in spring rate
- ~5 mm preload*
- 0.96 spring motion ratio
- 113 mm total damper stroke travel
- 25 mm bump stop length, of which 20 mm is usable*
- 880 lbs sprung corner weight

* = per Barry @ 3DM

Spring rate comes out to 343 / 25.4 = 13.5 lbs/mm.

880 [sprung corner weight] / 13.5 [spring rate] / .96 [motion ratio] - 5 [preload] = 62.9 mm suspension compression with car on the ground

113 - 25 = 88 mm damper stroke until bump stop engagement
113 - 5 = 108 mm total available damper stroke

So, roughly 25 mm damper stroke from rest until bump stop engagement, or 45 mm available damper stroke until things in the cabin get painful. Does that make sense?

343*.96 = 329 lb/in wheel rate
880/329 = 2.67" compression = 68mm. 5mm of that is preload, so 63mm of droop = exactly what you said.

So 45mm of bump travel, of which 20mm you're in the bump stop. Sounds like more bump travel would be good!

... I'd measure droop before doing anything, to verify.

[ultimatemj]

Curious what happened next...
I'm unhappy with my ride quality and my gut is the front is oversprung (8k(448lbin) which is mild by some but my understanding is stock ZCP is 3k(167lbin)...but my issue could just as easily be improper pre-load, so I've got some investigation to do.

[IamFODI]

Plan for the future: more bump travel.

Reasons:

1. Just hit the bump stops for the 3rd time since the install today. Horrible bumps -- far from the norm -- but if I can solve it, why not?
2. Calculations suggest I don't have much bump travel right now, and a ton of room to trade droop travel for it

I haven't taken any measurements; just calculated. Given:

- 343 lbs/in spring rate
- ~5 mm preload*
- 0.96 spring motion ratio
- 113 mm total damper stroke travel
- 25 mm bump stop length, of which 20 mm is usable*
- 880 lbs sprung corner weight

* = per Barry @ 3DM

Spring rate comes out to 343 / 25.4 = 13.5 lbs/mm.

880 [sprung corner weight] / 13.5 [spring rate] / .96 [motion ratio] - 5 [preload] = 62.9 mm suspension compression with car on the ground

113 - 25 = 88 mm damper stroke until bump stop engagement
113 - 5 = 108 mm total available damper stroke

So, roughly 25 mm damper stroke from rest until bump stop engagement, or 45 mm available damper stroke until things in the cabin get painful. Does that make sense?

[maupineda]

That's interesting because Shaikh from FCM has commented that a lot of well-regarded, high-end dampers run high pressure with large shafts. Whatever that means.

Yes, that is the same takeaway I took based on the testing FCM has shared on their youtube channel... basically, they add a lot of rebound force jacking the car down, plus the gas force, which makes the ride very harsh and fidgety.

[derbo]

BRA-Fing-VO 👏

I love the systematic process approach to the review and requirements. I also appreciate the transparency you have.

[IamFODI]

Do you know what your corner weights are?

With just me in the car and a full tank, sprung corner weights are something like:

880 865

855 830

But don't quote me because:

1. I only have rough estimates for the unsprung masses, and
2. I probably didn't set up the corner scales perfectly because I'm a noob.

What front and rear bounce frequencies did you target?

I didn't, really. See this post, after the italicized paragraph.

[duracellttu]

Do you know what your corner weights are? What front and rear bounce frequencies did you target?

[r4dr]

In my honest opinion, I'd say you have too high of a spring rate (front and rear), also most aftermarket add a lot of stiffness to their damper setup... my car even with softer springs (with 17% flat ride) still rides very harshly, and until I do something with the dampers, I won't get what I want. I just wish FCM was a bit more affordable.

That's interesting because Shaikh from FCM has commented that a lot of well-regarded, high-end dampers run high pressure with large shafts. Whatever that means.