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

[IamFODI]

Overview / BLUF

Mods:

- Öhlins Road & Track coilover dampers, stock valving
- Swift springs in stock Öhlins R&T rates (60 N/mm front, 120 N/mm rear)
- Turner Motorsport Hybrid camber plates (adapted by 3DM Motorsport)
- Syncro Design Works front tension arm monoball kit (pressed into new TRW arms)

I installed everything at once, so all driving impressions are for the setup as a whole.


What’s better than stock:

- Steering feel and feedback
- Compliance over broken pavement and sharp bumps
- Transient handling response
- Body control (no more floatiness)
- Some NVH (fewer jiggles, much less 80 mph vibration)
- Unsprung mass
- Driving fast


What’s worse than stock:

- Tire noise
- Impact noise
- Ride over medium-sized bumps and most road undulations
- Driving over some rumble strips
- Front bump stop hits (rare, thankfully)


What’s arguably better or worse than stock, depending on what you like:

- Turn-in
- Handling balance


Good experiences courtesy of:

- 3DM Motorsport / Barry Battle
- Öhlins
- Syncro Design Works
- FCP Euro
- Turner Motorsport (what’s left of it)
- Swift


Less-good experiences courtesy of:

- ECS Tuning


Boy, do I have things to say about this setup. This is going to be long, but I’ll break it up.

1. The Decision
2. The Camber Plate Saga
3. Parts Impressions and Weights
4. The Install
5. Initial Setup and Tuning
6. NVH
7. Ride Quality (addendum here if your roads are insanely bad)
8. Handling, Feel, and Feedback (updated w/ track impressions here)
9. Overall Verdict

[IamFODI]

The Decision

I was coming from completely stock, 110k mile old, non-EDC, non-ZCP suspension. Goals relative to that setup:

1. Quicker transient response
2. Comparably good limit behavior
3. General reduction of the feeling of mass in the car
4. Little to no lowering
5. No unnecessary NVH or ride quality compromises (can’t be unpleasant to drive or induce motion sickness in toddlers)
6. Equal or less weight vs. stock
7. Most likely to tick all those boxes in one shot

My car is my year-round daily driver, and this was meant to be a pure street setup. It’d be nice if it also happened to be a decent setup for the track, but that wasn’t a priority.

I’m running Michelin Pilot Sport 4Ss in the stock 18” sizes on 219Ms, and will be for the foreseeable future. As far as I can tell, that’s one of the quietest and most comfortable wheel-and-tire setups people run on this car, which means I have more room than most to firm things up before NVH exceeds reasonable limits.

Monoball-converted front tension arms were basically a given. The reviews suggested this was a must-do mod that’d do a lot to sharpen the front end with little or no downside. I considered Dinan and German Auto Solutions, but I picked Syncro Design Works because FCP Euro sells them. Lifetime warranty seems like a no-brainer for a monoball.

For springs and dampers, the Öhlins Road & Track kit was the default option and benchmark. There are a lot of reviews on this kit out there, and for street use they all seemed to be varying degrees of positive with few-to-no caveats. I had only experienced Öhlins Road & Track coilovers on an E46, but that was among the extremely few times when I’ve felt an aftermarket setup had OE-like depth-of-engineering.

I considered spring-and-damper packages (e.g. Dinan/Bilstein), but all of them lowered the car and none seemed likely to deliver enough improvement for the money/trouble. Other coilover/sleeve-over kits at or below Öhlins R&T prices all seemed to have fewer and/or less-uniformly-positive reviews for street use. Everything that seemed likely enough to be better than Öhlins was vastly more expensive; I had to draw the line somewhere, and this price point seemed like a sensible place.

When I sought feedback and then a vendor, Öhlins USA and multiple E9x/E46 people independently pointed to Barry Battle at 3DM Motorsport. He has a close relationship with Öhlins USA, including development work, and is seen as a go-to guy for the E9x platform. He spent a lot of time on the phone with me to talk through various options and educate me on various points. One of 3DM's options is the TrackDay kit, which comes with Swift springs (your choice of rates), camber/caster plates, thrust washers for the rear springs, urethane rear upper shock mounts, and all necessary replacement hardware. Barry also pre-assembles the kit before shipping (good labor saver), offers one free damper revalve, and provides above-and-beyond product support. The price tag on all this is not a dime more than the retail price of the headline parts.

EDIT: Since then, FCP Euro has started selling Öhlins suspension products. If this had been a thing before I made my decision, I might have been persuaded by the lifetime warranty to just go for it, like pretty much every time FCP Euro has something I want. In that case, I'd probably have foregone the Swift springs and camber plates, saved hundreds of dollars as a result, and made myself not worry much about what I was missing. However, having experienced the benefits of 3DM's pre-assembly and product support, and given how much I like the setup I have, I can't say I'd change the past if I could. And if I take Swift springs and TMS camber plates as a given either way, buying the Öhlins kit from FCP Euro would have meant a higher price tag and issues that I'd have been unlikely solve on my own. FWIW.

I evaluated a bunch of spring rate options for this kit. This was weirdly difficult. Very few people seem to second-guess the out-of-the-box rates in any coilover kit unless they’re hitting the track, and no one seems to do more than minor tweaking and minimal testing, so there’s basically no community knowledge on alternate spring rates for pure street use. All I could do was theorycraft based on forum feedback and generic suspension spreadsheets, and it seemed unlikely that I could trust that process to produce something better than what Öhlins’s development work had done.

To me, the only alternative that made sense to try was flat ride. I theorycrafted it out myself to the extent I could, sought what feedback I could get, and contacted Fat Cat Motorsports to see what they could do. I’ll spare the details of all the hypothesizing and hand-wringing I did, and of the discussions I had. The most important point is that, at the time I was looking into it, it seemed that no one including FCM had tried flat ride with non-stock springs on this platform. I had to assume it’d take significant trial-and-error to get the ride and/or handling right, and there was a small-but-nonzero chance that rare and/or custom parts might be needed. As much as I wanted to try it, I didn’t want to be among the first – especially at a significant price premium over a known-good option.

So, default Öhlins spring rates it was. Fortunately, Swift’s catalog has those rates covered in the appropriate dimensions (65 mm ID, 178 or 203 mm (7” or 8”) length front, 254 mm (10”) length rear). Per Barry, the Swift fronts are almost 2 lbs lighter than Öhlins’s fronts.

The one change I really wanted to make to the kit was the camber plate. The kit normally comes with the Vorshlag plate. All the feedback I’ve seen on it suggests it’s a great piece. What gave me pause is that its monoball is unsealed and purely metal-on-metal. I didn’t like the idea of an unsealed monoball for a year-round daily driver in the NE US. And with that plus the front tension arm monoballs, every joint in the front suspension would be fully solid or close enough (the Syncro Design Works monoballs and many BMW ones are apparently nylon-lined). Seems fun to me, but likely not sensible for a family car.

The Ground Control Street plate was the sensible alternative. People seem to love it. But I saw mixed reviews on the durability of their bushings and hardware, and I didn’t want to risk frequent replacements on a DD that could see up to 20k miles in a year.

Enter the Turner Motorsport Hybrid camber plate. Its monoball is sealed and polyurethane-isolated, preserving most of the benefits of a monoball with fewer downsides. Obioban has used this plate back-to-back with the GC Street plate on his E46 and noticed no meaningful NVH difference. And the polyurethane bushing is boxed in on all sides and not load-bearing, which should reduce or eliminate the usual problems with polyurethane. Seemed like another no-brainer... right up until I decided to go for it. (spoiler alert: the item is fine; the process was just annoying)

[IamFODI]

The Camber Plate Saga

Selecting the Turner Motorsport Hybrid camber plate was easy. Obtaining and implementing it was frustrating. From day one through the install, there was a drip-drip of easily solved but stupid issues that needlessly delayed the project by weeks, for which ECS showed little-to-no accountability.

As of this writing, when you use the navigation on TMS’s website to pull up E9x M3 parts, this is the product page for the Hybrid camber plate that comes up. It states that it’s for OE and OE-style springs. It felt weird to think they’d make a camber plate that couldn’t accommodate normal coilover springs, so I contacted customer support and asked them if it’d be compatible with the 65 mm ID springs I’d be using. It took some effort to get an answer. One rep even tried to steer me away from the Turner plate toward KMAC (better luck next time, bro). However, when the answer finally came, it was an unqualified yes. I shared this with Barry, and we pulled the trigger.

When the TMS Hybrid plates showed up at 3DM (after a considerable shipping delay), the spring perches were clearly for OE-style springs and would not fit the Swift springs. We contacted ECS support again. Only then did they reveal to us a completely different version of the product page for the camber plates that lets you select the correct upper spring perch option. This page was not visible when navigating the site by application because it didn’t have any applications associated with it. You couldn’t even see it unless you used the text search on the site or received a direct link. That remained true as of this post's original date – though they have since replaced both pages with a single one that allows you to select spring perch options.

Our options were to buy TMS’s perches, gank some off another camber plate set somewhere, or fabricate some (3DM can do that). Somewhat puzzlingly in retrospect (though it made sense at the time for reasons that aren't worth getting into), we chose to buy the TMS ones. At the time, ECS refused to accept a return on the incorrect perches and offered nothing in consideration of having screwed up. Leaving space here for someone to correct the record if they changed their minds about this.

When the correct spring perches arrived (after another considerable shipping delay), their thickness plus the plates’ higher damper rod position meant that the front springs we had ordered were too long for comfort. The stack height pushes the spring down and the higher damper rod position pulls the damper up, leaving too little room between the upper spring perch and the anti-roll bar bracket to accommodate a 203 mm / 8” long spring without almost an inch of preload. So, we selected one-size-shorter springs – 7"/178mm. That size fit just fine, though I later discovered this leaves basically no room to add preload without coil bind.

Furthermore, some of the camber plates’ hardware needed to be modified to fit the dampers. The mods involved spacing the damper rod down a bit and finding a way to locate the dust boot without the provided washers (which wouldn't fit inside the springs). 3DM handled all of this with ease, but it still meant more delays and more potentially non-returnable parts. Whether these issues were ECS’s “fault” is debatable, but they sure seem like things that Vorshlag and Ground Control have no trouble preventing. They put all the relevant hardware options online, and they make it relatively easy to get measurements and talk to someone who can fill in the few remaining blanks. With ECS, the info online and from support contacts was incomplete or inaccurate until we raised enough of a fuss, waited long enough on hold, and/or simply had enough luck to speak with someone who knew what they were doing.

ECS even got the camber plate mounting nuts wrong. Their flanges were too wide for the slots in the strut tower brace brackets. To ECS’s credit, they actually stepped up here, sending out a set of OE nuts directly to me at no charge. Those shipped and arrived in short order. Too little too late on ECS’s part, but still pretty refreshing after the rest of the experience. And I like the OE nuts better anyway because their skirts help line up the strut tower brace bracket.

In sum, if you choose to run Turner Motorsport Hybrid camber plates with Öhlins Road & Track coilovers and 65 mm ID springs:

1. Make sure you use the right product page to order the plates with the right perches;
2. Know that your spring options are 8"/203mm with a ton of preload or 7”/178 mm with basically no stroke travel to spare; and
3. Make sure ECS sends you the right hardware for your dampers and spring perches, or be ready to do some grinding and tinkering.

And for anyone from ECS Tuning who might be reading this:

1. You’re welcome for the free R&D and product support, and
2. If you don’t like people thinking you pillaged and destroyed Turner Motorsport so you could milk their brand while burying their products and expertise under a truckload of mediocrity, you’ve got some work to do yet.

[IamFODI]

Parts Impressions & Weights

(Note the labels on the rear dampers. 3DM Motorsport provided me dyno plots for each damper; the rears look identical, so Barry labeled them so I knew which plot was for which damper.

Everything looks and feels awesome. Strong impressions of quality all around. The damping adjusters especially feel like works of art.

The only exception is the rubber isolator for the rear height adjusters. It’s super thin, as is the step in the height adjuster that’s supposed to locate it, so it’s almost impossible to keep it in place during the install unless you completely unbolt the camber arm and/or have help when bolting everything back up. Kind of surprising for an Öhlins part.

On the front struts, I kind of felt like the lower mounts should have locking collars to keep them from moving during install. Locking collars really aren't necessary, though, and omitting them provides a negligible-in-practice but high-nerd-value reduction of unsprung mass.

The TMS camber plates are surprisingly thin, at least to my noob eye. Between that and their high damper rod mounting position (in unmodified form), they're clearly designed to provide as much bump travel as possible. Seems like a nice piece for lowering on stock and stock-replacement dampers.

The front tension arms with Syncro Design Works monoballs looked pretty much as they should, the only exception being some scratches down to the base metal on the bearing housings (presumably from the install into the arms). Not really an issue though, because you’ll never see them and… lifetime warranty.

I weighed the tension arms and coilover assemblies prior to install, and the OE parts after pulling them. The weights below include whatever hardware is necessary to hold the assemblies together, but they do not include mounting hardware as that’s common to both sets. I weighed the rear springs separately from the upper perches/height adjusters because the latter are entirely sprung (another nice feature of the Öhlins setup), and I wanted to keep track of sprung and unsprung masses separately where possible.

I used my Brecknell postage scale for everything except the front coilover assemblies, which were too heavy. I had to use a bathroom scale for those, so the numbers should be taken with a grain of salt, though the difference between OE and Öhlins is probably accurate enough.

OE front tension arm: 3.4 lbs
TRW front tension arm w/ Syncro Design Works monoball: 4.7 lbs

OE front coilover (non-EDC) w/ top mount: 13.2 lbs
Öhlins Road & Track front coilover w/ Swift spring & TMS camber plate: 11.4 lbs

OE rear damper assembly w/ OE top mount bushing: 5.1 lbs
Öhlins Road & Track rear damper assembly w/ urethane top mount bushing: 4.5 lbs

OE rear spring w/ lower perch: 6.9 lbs
Swift rear spring w/ lower perch & Swift thrust sheet: 4.9 lbs

OE rear upper spring perch: 0.9 lbs
Öhlins rear height/preload adjuster w/ Swift thrust sheet: 1.0 lbs

All-in, that’s a net decrease of roughly 0.5 lbs per front corner and 2.7 lbs per rear corner. Not exactly monumental, but I’ll take it. Hard to improve on OE when it’s already aluminum. Apparently it's not uncommon for aftermarket suspensions to add weight, so to lose any at all is nice. At least the mass in front has shifted lower and inward! (more in the tension arm monoballs, less in the coillovers)

Nice touch: 3DM put all the hardware in separate labeled bags.

[IamFODI]

The Install

I followed multiple DIYs, guides, and other resources for this project. Few were directly related to my exact mods, some weren’t even specific to the E9x M3, and many involve products I dislike, but they all helped somehow. I’m sure I’m missing some, but here’s what I can recall:

1. Torque specs: https://www.m3post.com/forums/showthread.php?t=1330067
2. Good DIY on front tension arms and control arms: https://www.youtube.com/watch?v=JhDv5GEWlOY
3. Not even E9x, but this guy's explanation reinforced the fact that you don’t have to hold the tension arm balljoint stud while torqueing the nut, which blew my mind: https://www.youtube.com/watch?v=_An0EkkwI6U
4. I feel dirty: https://www.youtube.com/watch?v=4YkVs_jm9R4
5. Even dirtier: https://www.youtube.com/watch?v=wTP1oQ424rM
6. Need a shower: https://www.youtube.com/watch?v=xZmPLvhUZpY
7. Another misc. video: https://www.youtube.com/watch?v=lXdyTrg_GQM

Suffice it to say there’s a wealth of resources out there and I won’t pretend I can do better. I’ll just offer some comments on some peculiarities.

I’ve seen it written that the front anti-roll bar end link studs need a slim 16 mm wrench on them while you remove the nuts. Mine took 19mm, and it didn’t have to be slim. Not sure what that means, but there it is.

On the front tension arms, the lock nuts on the balljoint studs really did not want to come off. The stud threads had a lot of rust – par for the course for a >110k mile daily driver in the NE US. I could turn the nuts with a lot of effort, but only until the nylon reached the rusty top threads on the stud. The moment they reached that point, they might as well have been welded on. The solution was fire. I heated the nut to melt the nylon, turned it until the nylon solidified and the nut re-seized, and then repeated until the nut was free. It took patience but it worked. Of course, I only figured this out after stripping the Torx hole in one of the studs. Nothing to do there but cut it out.

(Still a better love story than Twilight)

When installing springs and dampers, most of the nuts and bolts you remove are supposed to be replaced. I didn’t want to replace them all multiple times (initial setup, corner balancing, alignment), so I re-used all the originals at first with some Loctite and more-than-spec tightening torque for good measure. I saved the new hardware until after the ride height tweaking, corner balancing, and alignment were all done. I can't recommend this to anyone for obvious reasons, but evidently I lived to tell about it.

In the rear, when (partially) unbolting the camber arms, I opted not to touch the eccentric bolts so that I wouldn’t mess up the rear camber. That made it slightly more annoying to install the new springs and height adjusters, especially while trying to keep the rubber isolators in place, but I made it work.

A note about the rear dampers: before you install the lock nut for the top mount, it’s best to set the damping to full stiff before removing the adjuster. The damping adjuster works by turning a set screw just inside the top of the damper rod. The softer you set the damping, the higher up (and looser) that set screw is. At softer settings, it’s high enough that there isn’t enough room for an Allen tool to hold the top of the shaft while you tighten the top mount lock nut. And if you accidentally loosen the set screw all the way, it might pop out without the adjuster in place above it. It’s so small that you might not even know you’ve lost it until you go to adjust your damping (3DM sells spares if you do lose it). It’ll click because the detent is in the adjuster itself, but it won’t change anything without the set screw. So, again, set the damping to full stiff before removing the adjuster. That’ll keep your set screw in place and give your Allen tool plenty of purchase.

[IamFODI]

Initial Setup & Tuning

After the initial install, the plan was:

1. Slow drive around the block to settle everything and listen for noises
2. Measure ride height, adjust accordingly
3. Another slow drive; repeat from previous step if necessary
4. Test drive
5. Try out some damping settings
6. Corner balance (badly because I’m a noob)
7. Alignment
8. Replace all one-use fasteners with new

Because the springs and camber plates were all different from what comes with the Road & Track kit, I had to completely disregard Öhlins’s recommended measurements (except the ones for the rear damper bodies, which Barry assembled before shipping). Not a problem; it just meant the install took a bit more trial-and-error.

There was a neat coincidence on the front struts. When I lined up the bottom of the threads on the “gold cup” height adjusters (which actually start about 8 mm up from the bottom) with the bottom of the damper bodies’ threads, I ended up just over stock ride height. Lowering the suspension from there was fairly straightforward; the front strut’s motion ratio is close to 1, which means shortening the damper body by X lowers the car by just-over-X. Or you could use the Öhlins guideline of 1 turn = 1.5 mm ride height. I guess this is the flip side to the weird dimensions of the TMS camber plate, combined with the Öhlins R&T kit and Barry’s mods; you end up with a convenient way to get roughly-stock ride height, which is also a convenient jumping-off point for whatever ride height you eventually want to set.

The rear spring motion ratio is ~0.57. So, when adjusting rear ride height, take the wheel-to-fender adjustment you want, multiply that by 0.57, and that’s how much you need to adjust the upper spring perch. For example, if you want to drop the height by 10 mm, you have to raise the upper spring perch by 10 * 0.57 = 5.7 mm. This is a function of the car’s rear suspension, not the Öhlins kit, so it’d apply for any rear height adjuster.

I haven’t driven enough to be able to say I’ve found my favorite damping setting yet, but so far I’m liking 5 clicks from max all around. I started with the adjusters at full soft and increased it from there, on one axle at a time, until excess motion stopped decreasing. Over the next few months, I’ll probably try some more settings and see if I change my mind. Happy to take any recommendations.

The install preserved the suspension’s alignment so well that I almost reconsidered having an alignment done. The car drove dead straight. I did of course still take it in for an alignment (Bimmerworks in West Chester, PA), but it needed only minimal adjustments. I’m not sure they even touched the camber plates. The minimum settings, which TMS says are “closest to OEM specification”, yielded very close left/right camber values and almost identical left/right caster values, all of which were only slightly higher than stock – pretty much what I wanted.

[IamFODI]

NVH

Again, I’m running Michelin Pilot Sport 4Ss in the stock 18” sizes on 219Ms. Can’t say any of this applies to any other tires.

Forum reviews suggest that all the components of this kit add little or no NVH over stock. Either those reviews are too optimistic, or all the mods together yield more NVH than if you add up each one’s contributions on an otherwise stock suspension. I’m guessing all of the above. Either way, this setup is significantly noisier than stock.

At the same time, it’s not nearly as bad as it could be, and I find the extra NVH completely tolerable given the benefits.

There’s more impact noise and a lot more road noise, but it still feels within reasonable limits for this kind of car. Most of the added noise is like pink/brown noise, which is not hard to take. The most bothersome kinds of NVH – the kinds of noises and jiggling that make a car feel brittle and cheap – have decreased, if anything. The old suspension used to jiggle just slightly on some bumps, and there was a hint of classic 80 mph vibration even after Road Force balancing the wheels. The jiggle is now extremely rare and slight. The 80 mph vibration is greatly reduced.

This is amazing to me because, in one important sense, this setup is more extreme than most people would do for a street car (let alone a daily driver): it eliminates all the rubber in the front suspension’s load paths. Other than the nylon lining in the ball joints and the thin polyurethane bushings around the camber plates’ bearing housings, everything is metal. This setup had every right to be a total NVH shitshow.

Somehow, it isn’t. If you can tolerate the extra impact and road noise – which, if you own this car in the first place, you probably can – you’ll probably find them an easy price to pay for the benefits.

The only possible exception is rumble strips. I say "possible" because most I've encountered have been fine, except for one that I never hit on the stock suspension -- but that one made me feel like I was inside a vibrating smartphone, and I have a very hard time imagining this suspension didn't contribute. FWIW.

[IamFODI]

Ride Quality

Had to tick three boxes here:

1. No more driving fatigue than before
2. No more wife complaints than before
3. Kids able to fall asleep in the back

So far, so good on all counts. I haven’t noticed any more fatigue than usual, my wife doesn’t notice a meaninfgul (to her) difference from before, and my kids can still sleep.

Notwithstanding my family's indifference, I’m not going to pretend the ride is “like stock” or whatever. It isn’t, for better and for worse. Medium-sized bumps hit harder, and the car closely follows undulations in the road that the stock suspension would glide over. But it also rounds off sharp bumps and irons out broken pavement way better than stock, and there’s a lot less crashing and excess body motion. The car feels really tied-down everywhere. The worse-than-stock aspects only took a few hours of drive time to get used to, and I almost don’t even notice them anymore unless I'm looking for them. And at highway-plus speeds, the combination of smooth and tied-down is magical compared to stock. It eliminates distractions and confidence-sapping body motions while still letting you feel the road surface so you can focus on what you’re doing.

I really had to recalibrate my mind for this kit. On some okay-but-bumpy roads, the ride is firm enough to make you worry that seriously broken pavement or big bumps/dips on the highway could be catastrophic. Then you get to a stretch of road with that really bad stuff on it, and the car is a pussycat. It's not a pleasant experience, but it doesn't ruin your day.

On one stretch of highway I travel regularly, there’s a dip immediately followed by a slight crest, right at the entry to a corner. On stock suspension, the car would crash in the dip and then float after the crest even at normal-ish speeds. I was always scared that if I went too fast, I’d bottom out and then fly into a barrier. I’ve driven over that same irregularity a bunch of times with the new setup, and a few times I forgot it was there. The difference is astonishing.

One thing I’m not sure how to assess is pitch. I am feeling a bit more than stock, but I can't tell whether it's from a lack of pitch stability or simply the car following the road more closely. All I can say for sure is that there’s none of the gross porpoising I’ve experienced in almost every other aftermarket suspension I’ve had real seat time with. The vast majority of the time, the car rides flatly enough that my noob self can’t clearly discern a problem. Hoping to try a well set-up flat ride setup in one of these cars one day to compare. At a bare minimum, I think this kit provides strong evidence that a car can ride flatly without “flat ride” spring rates – though you might still pay a price in the form of less compliance if a lot of extra damping force is required to get there (which might well explain a lot of the firmness in this setup).

EDIT: If your roads REALLY suck – like, COVID neglect plus winter – this kind of setup might not be a good call.

[IamFODI]

Handling, Feel, and Feedback

Predictably, the real payoff is here.

The steering feels like a tighter, heavier, more communicative version of stock. This was already one of my favorite parts of the car, and now so much of what I liked about it is even better. It’s fantastic. I wish I had more to say on this without being repetitive because it's hugely impactful on the driving experience as a whole.

There might be a bit more bump steer up front. But if there is, it's not by much.

Some one-wheel bumps seem to tug the rear end sideways more than they did before. Maybe that’s due to stiffer springs and dampers revealing/exaggerating the effect of worn bushings, or something. Interested to hear thoughts on this. EDIT: Not an issue after correcting tire pressures.

Overall body control is in a completely different league. The stock suspension, especially after so many miles, felt a bit floaty and floppy in transitions. I don’t want to make that problem seem worse than it was; it didn’t make the car feel like an econo-SUV or anything. It just took the edge off steering inputs more than I'd like and introduced delays in the chassis's responses. It was a confidence sapper in corners, as well as an exclamation point on the fact that this car is several hundred pounds heavier than I prefer. That feeling is gone now – or at least reduced to a non-issue for the kind of driving I do. I feel like I don’t have enough tire to unsettle the suspension, and that’s how I want it. The car feels an order of magnitude more confidence-inspiring in a corner. It still feels a lot heavier than I like, but it’s not rubbing my face in that fact the way it used to.

Handling balance has changed exactly as one should expect from the spring rates: more understeer / less oversteer / more rear grip. Classic result of bumping up ride frequency far more in front than in rear. I’m assuming this is why the steering response doesn’t seem any pointier than stock despite the drastically reduced compliance. I’m a little disappointed with that lack of pointiness; I was hoping for a more positive-feeling front end than I ended up with. But the car seems to get out of a corner much better, and oversteer is still accessible in every sense of the word. Overall, I’m not going to call this better or worse than stock because that depends on what you like. What I can say is that it’s a sensible balance and I’m enjoying it. It's nice to be able to lean on the rear end more while still being able to play with it.

The overall effect is that the car is much more fun to hustle than it used to be. It feels night-and-day better in transitions, gives better feedback, is even friendlier at the limit (as far as my noob self can tell), and inspires a ton of confidence. And crucially, the improvement over stock feels bigger the faster I go.

EDIT: track impressions here!

[IamFODI]

Overall Verdict

- Quicker transient response than stock: Check.
- Comparably good limit behavior to stock: Check.
- Less feeling of mass: Check. Not enough to make me stop missing a lighter car, but enough for now.
- Stock ride height or close to it: Check.
- Reasonable NVH and ride quality: Close, but check.
- Equal or less weight vs. stock: Check.
- All boxes ticked in one shot: Check.

It’s not perfect. Somehow, I don't think it evinces the depth of engineering of an OE setup. If BMW had implemented dampers like this and optimized for this level of transient response and feedback, I'm sure they could have done a better job -- if only making it feel a bit less rough-around-the-edges.

Either way, a win's a win. I'm happy.

[Obioban]

Now THAT is a suspension review!

[r4dr]

This is the quality content I'm here for. Did TCK dampers appear in your thought process at all?

[IamFODI]

Did TCK dampers appear in your thought process at all?

Yes. Nice products with a great rep. They just didn’t seem like enough of a leap. I wanted something with a blowoff of some kind. Also heard from Obioban, who had run both on the same car, that Öhlins had the edge in a performance setting (though they were close overall).

[BMWahba]

Barry at 3DM is a great guy. He set me up with a similar setup for my e46. If anyone is looking to buy Ohlins, 3DM is the way to go for sure!

[tdott]

Great review!