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M2 Technical Topics > Suspension | Brakes | Chassis > Sachs Performance Coilovers on M2C / Install and first impressions

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      04-21-2020, 08:20 PM   #1
x233
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Sachs Performance Coilovers on M2C / Install and first impressions

What I was after: a coilover kit suitable for inclement weather (dust boots, reliable adjusters), use of OEM top mounts, a moderate drop (20-30 mm), height and rebound adjustable, monotube design, ease of adjustment, improved handling, acceptable comfort, reasonable price.

What the car is used for: mostly spirited driving in the city, some medium to high speed driving on twisty&bumpy country back roads, and occasionally high speed highway; sometimes loaded (wife + 2 kids +/- bags).

Narrowed it down to Bilstein B16 PPS10, Sachs Performance Suspension Kit, Eibach Pro-Street Multi. The latter two seem to be the same kit, packaged by Sachs or Eibach.

https://www.sachsperformance.com/bil...500.000484.pdf (Sachs)

https://media.carparts-cat.com/pdf/E...E692003101.pdf (Eibach)

Monotube shocks / upside down
Front spring is progressive, rear is linear
Front axle spring rate: 48 N/mm (pretty sure both front and rear are softer than the stock)
Rear axle spring rate: 120 N/mm
Spring height and preload adjusted simultaneously
Single rebound&compression adjusters on the bottom of the shocks / 20 clicks from closed to open
OEM top mounts
Dust boots




At the moment, the car is 12 days past install, several height and rebound adjustments, and two wheel alignments. The installation was done at an indie shop per product and BMW manuals (https://www.newtis.info/tisv2/a/en/f...pair-manuals/)

What was not done - didn't replace the original bolts and nuts (recommended) except for the front top strut mount nut which came with the coilover kit. Tried to be careful to keep the original hardware.

One difficulty we run into was the rear shock top mount nut. It has a peculiar form and access to it is somewhat difficult. We didn’t have a special tool that fit so we had to weld one from parts in the shop and had to be extra careful with that one.

Took much longer to get a workable height, rebound and wheel alignment. Both Sachs and Eibach state the expected drop between 25 and 50 mm on both axles but it is simply not possible within the range of adjustment permissible per product certificate. The actual drop possible if done within the permissible range is up to 30 mm for the front and about 20 mm for the rear.

(similar to Bilstein and Ohlins, it seems the kit was design for M3/M4, M2/M2C being an afterthought when they came out. The range of adjustments per certificate presumably reflect what’s expected of M3/M4)







Height

Turning spring perches and locking them in place is easy, front and rear, when the car is on a lift. You have to remove the front wheels to do the front, and you don’t have to remove anything in the rear.

Still, getting the right height is a tricky part because of the limitations of the coilover kit per se, and because it’s hard to judge the exact lowering immediately after adjustment. It takes a while to settle. Moving it and driving it immediately after install isn’t enough. It doesn’t settle evenly and you may be off your target a few days later. It takes multiple tries and days.

Also, there are 2 kinds of references ranges to respect per certificate:

1) front spring perch where it meets the spring to the pinch bolt on the hub (permissible range is 165 - 205 mm) / vehicle frame to the cap of the spring seat in the rear (permissible range is 10 - 40 mm)

2) wheel arch to the center of the wheel ( 330 - 360 mm in the front, 325 - 360 mm in the rear)

The measurements of the vehicle height before install (OEM method, from wheel arch to the bottom of the wheel / tank ¾ full): front left 620 mm, front right 622 mm, rear left 620 mm, rear right 620 mm.

After the initial install and some fiddling around the first day, we got 590 mm in the front and 600 mm in the rear. That’s 30 mm drop in the front and 20 mm drop in the rear and a 10 mm rake which was not intended (I thought maybe 5 mm rake but couldn’t get that). Tried raising the front half a turn further while lowering the rear half a turn… for some reason the front only got higher 1-2 mm while the rear got higher, too, a couple of mm… Strange… and it takes time to get it right.

When you are 30 mm down in the front that’s already 330 mm from the wheel arch to the center of the wheel. So, if you are to respect the certificate range you can’t go lower than 30 mm. Tried a lower front (in fact it’s 5-10 mm lower than that if you leave the factory preset spring perch height) which produced super sharp steering but in a tight speedy turn the front plowed and it felt like the front didn’t have enough travel so we backed off.

28-30 mm front drop seems like what it takes to get it right. (also, 30 mm drop is what it takes to crawl over some speed bumps near my home)

The rear: that’s we ran into another issue. The range of adjustment is supposed to be 10 - 40 mm. With 20 mm it’s about stock height, so there’s only about 10 mm of adjustment range. I would gladly disrespect that and try lower but…

Issue: when we lowered the rear 20 mm (that’s about 12 mm from the spring cup to the frame) with the car still on the lift and the wheels hanging freely the left rear spring is firmly in it’s place but the right rear spring is a bit loose: Can’t really move it in the axial direction yet but I can wiggle a little from side to side.

Can’t understand why. The car is relatively new (19,000 km), the condition of the OEM rear top and bottom spring seats, and all other suspension parts seems OK on both sides… removed both rear springs, seemed to be assembled and seated correctly, double-checked the distance from the spring cup to the frame… I am puzzled.

(may have to replace OEM rear spring seats in the rear to be sure, perhaps some other parts… don’t know…)

Afraid to turn the right rear spring any lower because I am afraid it might get loose under some (extreme) driving conditions in a situation when the right rear suspension is completely extended. I don’t know if it’s safe to try. If not for this I could maybe get another 5 mm drop in the rear (which is what I so wanted)…

At the moment, the rear is some 10 mm higher than the front. Also, for some reason after the install the whole left side was some 3 mm higher. It took several days to settle evenly in the back and 2 mm higher in the right front (same as before the install).

The rear is begging to be a bit lower to be more controlled on imperfect undulating back roads.

Wheel clearance / Rubbing

At full lock with the stock wheels and no spacers at 30 mm drop in the front there is no rub but it may rub if spacers are used in the front. At full lock with a slightly used Michelin PSS 245/35/19 tire there is only about 7 mm clearance from the front fender liner.

With the lowering of 28 mm or lower in the front the outer shoulder of the front tire may rub against a protrusion inside where the bumper is bolted to the fender. I had that happen 2 times to my right front when slamming on the brakes in a road dip before jumping out of it at high speed, a paint mark on the tire shoulder. So you have to either shave some of that off or raise the front a bit.

It’s tight and there may be problems with other tires/sizes.






Rebound&compression Adjustment / Handling

In the front you turn the wheel full lock, kneel, reach behind the wheel and turn the knob, same for the other side. In the rear it’s less convenient but you can still do the job. The turns are not too tight and the clicks are distinct.

The factory preset is 10 clicks open all around. That’s comfortable around the city but you need at least 1 click harder in the front to counter understeer and make handling more consistent. With default settings and slightly raised rear (as in my case) the rear may feel floaty if you go fast and there is a noticeable change in the brake balance toward the front.

(I drive almost always with MDM enabled, sport or sport plus, gearbox either D1 or S3 when in manual, steering set to comfort)

For the city, back roads, and for speeds up to 160 km/hr (or 100 mi/hr) I chose +3 harder in the front and +1 harder in the rear as the most appropriate setting (aka my default setting).

With these settings the handling is sublime and playful. The steering is a bit tighter, is sharp, but may be a bit sensitive at high speeds so you are more aware of the speed than with the stock suspension, the car licks tight corners and dives into tight spaces easily, rotates under throttle, there’s brake tailing when you need it. The whole process of driving is more fluid. This simply was not there with the stock suspension. I noticed that my driving became more aggressive and it’s not necessarily because I’m trying. I’m more conscious of the rear end, though.

For high speed driving (over 160 km/hr, or 100 mi/hr), or driving loaded with passengers and bags, or driving on really crappy roads, tightening the rear shocks a bit (to +2 harder). This works for speeds up to 200 km/hr (or 125 mi/hr). Tightening the rear just one click (+2 from the preset 10 open) makes the car more stable.
+4 clicks in the front and +2 clicks in the rear gives a car a good overall balance but, unfortunately, feels too tight for the city, the steering and everything.

_________________________

Comfort

At +3 harder front and +1 harder rear the suspension is perfectly comfortable (compared to the stock), compliant and balanced, and deals with minor and medium imperfections better, not nearly as jarring as the stock. At +4 harder front and +2 harder rear it’s definitely tighter than the stock and you can feel all road imperfections more, although still not too jarring, but too tight to steer even in comfort mode.

Noise: usually perfectly quiet, but there may be an occasional muted clunk coming from the front driver’s side or somewhere in the rear on particularly crappy roads and some bad bumps. (not sure what makes that sound)

_________________________

Wheel alignment

Initially, decided to go with the front toe in 0.03` symmetrically, front left camber -1.15`, front right camber -1.32`, rear toe in 0.07` symmetrically, rear camber -1.55` symmetrically.

This, especially with the preset soft rebound settings of the rear shocks didn't work well at all. On my first drive out of a gas station, and it was a cold day at 4 C (39 F), with the usual throttle application I was caught off guard going sideways. The rear felt too loose. Also, the rear was noticeably worse putting the power down and squiggly under throttle.

One week later the alignment was off as the suspension had obviously settled, and settled unevenly: the front toe in still 0.03` symmetrically, but the rear toe in was now 0.06` and camber -2.10 and -1.57.

Decided to leave the front as is at 0.03` toe in symmetrically (perhaps too optimistic for the street?) but to compensate for the unstable/soft/raised rear and to help traction the rear was set to 0.09` toe in symmetrically and camber to -1.35`.

This helped a lot. The rear became stable, not really squiggly under throttle anymore, no unintended sideways tricks, and the traction is now comparable to the stock, also available out of a turn.

Did some aggressive driving on the back roads and took note of the scrub lines on the front and rear wheels - much better. Before, the outer shoulder of the rears was hardly working. Now, it’s better but still not perfect. Measured the temperature of the thread with… my fingers: the fronts were OK, the rears’ inner blocks were noticeably warmer than the outer shoulders. Which means when I do an alignment again it’s safe and probably better to go with even less camber in the rear (thinking about -1.30` and probably 0.10` toe in) - going to be still better putting the power down and having a slightly more stable rear end.

Rear


Front



Traction

With the initial alignment it was really suboptimal (running tire pressure 2.40 bar front and rear), the stiffer the rear shocks the worse.

After my second alignment the traction is OK with the factory presets of compression/rebound 10 open, still fine if you go a bit harder (+1, +2 or +3 harder from the preset), but would probably get bad if I went yet stiffer on the rear shock settings. I want a bit better traction.

_________________________

Thoughts:

Wish the spring rates were a bit higher. I don’t take the car to the track but still... Probably wouldn’t have a front rub. Probably would benefit from slightly stiffer springs all around.

Wish there was one setup that fit all possible scenarios. It’s easy to turn a couple of knobs to get it right for a particular occasion but I still wish there was one universal setup. Perhaps, I’ll get one if I manage to lower the rear a bit more.

Going to raise the front a bit, and probably still need to shave off that inside fender bulge where there’s a rub, and see if I can get the rear any lower, and to slightly fine-tune the rear wheel alignment.

Thinking of how to lower to the rear more... Not sure it’s safe to try to lower the rear on the current installation with the current parts, say half a turn of the spring perch… just not sure.

Also, wondering if some OEM aero for the rear could possibly improve the high speed situation without having to tighten up the rear.

_________________________

If anyone has any thoughts on where I possibly messed up, or things to try, comments are welcome.

Last edited by x233; 04-22-2020 at 02:07 AM..
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      04-22-2020, 01:07 PM   #2
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Thanks for the writeup on these coilovers. I've been interested in seeing people's impressions of Sachs/Eibach's kit.

Quote:
Originally Posted by x233 View Post
Still, getting the right height is a tricky part because of the limitations of the coilover kit per se, and because it’s hard to judge the exact lowering immediately after adjustment. It takes a while to settle.
One thing to consider about when adjusting the height is the spring to wheel motion ratio. This means for every Xmm of wheel travel there's Ymm of spring travel/compression. When I'm dialing in my ride height I usually measure how much I want to lower at the wheel, and then calculate how much that equates to at the spring. This typically gets me very close to the actual setting.

Quote:
Originally Posted by x233 View Post
Front spring is progressive, rear is linear
Front axle spring rate: 48 N/mm (pretty sure both front and rear are softer than the stock)
Rear axle spring rate: 120 N/mm
The front is a good bit stiffer than the F87 OE springs, but the rear is similar (slightly stiffer). It looks to me they aimed to make the front and rear ride frequencies equal to each other instead of maintaining a flat ride ratio that the OE suspension had where the front frequency is lower than the rear.

Going to flat ride would probably help your high speed stability issues since the chassis would settle faster. With a pitch/non flat ride frequency setup you have to rely on higher damping (overdamping) to keep things under control. Your own experience shows this when you mentioned at higher speeds you have to turn up the damping settings (which then hurt ride quality too much).

If that's something you want to play around with in the future you can try putting different stiffer springs in the rear. Sometimes coilover kits can accept standard 60/65mm, 2/2.5" coilover springs, or there are cheap enough adapters to use them with.

Here's a video where we changed the springs on a Bilstein B14 kit to produce flat ride. The original springs had a higher front ride frequency than rear.
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      04-22-2020, 08:30 PM   #3
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Quote:
Originally Posted by FaRKle! View Post
Going to flat ride would probably help your high speed stability issues since the chassis would settle faster. With a pitch/non flat ride frequency setup you have to rely on higher damping (overdamping) to keep things under control.
Thanks for your input. That's exactly my problem. I, too, think the rear is too high at 10 mm vs the front. I would like to (almost) flatten the ride by lowering the rear but I am not sure I can lower much further because the right rear spring already feels a bit loose when the rear suspension is completely extended (the wheel hanging). Don't know what a safe margin would be.

(I intend to raise the front a tiny bit but I really don't want the raise the front the whole 10 mm)
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      04-23-2020, 12:44 AM   #4
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Quote:
Originally Posted by x233 View Post
Thanks for your input. That's exactly my problem. I, too, think the rear is too high at 10 mm vs the front. I would like to (almost) flatten the ride by lowering the rear but I am not sure I can lower much further because the right rear spring already feels a bit loose when the rear suspension is completely extended (the wheel hanging). Don't know what a safe margin would be.

(I intend to raise the front a tiny bit but I really don't want the raise the front the whole 10 mm)
You can try to add a helper spring and coupler to the rear spring so it stays put and doesn't come loose under droop.
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      04-23-2020, 03:44 PM   #5
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Quote:
Originally Posted by FaRKle! View Post
You can try to add a helper spring and coupler to the rear spring so it stays put and doesn't come loose under droop.
I kind of think the manufacture should know better that their product works as is (or is supposed to work) without going too far away, or at all, from the original design. So I think it's probably me who cannot yet find the right settings rather than something wrong with the product. So I'll try to figure it out.

(lowered the rear 2 full turns of the spring perch today, 1 turn is 2 mm on the perch, we'll see how that translates to the wheel drop; also, turned the front 1 full turn of the spring perch. I am going to drive it a bit tomorrow and make final measurements and see what I've got... / first I dropped the rear and drove that way a couple of blocks, the rake was still there so I raised the front... half a turn (180 degrees) - liked that, another half a turn... not so much. but I need it to settle and I need to drive a bit more).

update: 1 turn of the rear spring perch or 2 mm height at the spring = 2.5 mm drop at the wheel.

Last edited by x233; 04-24-2020 at 10:29 AM..
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      04-25-2020, 09:19 PM   #6
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Lowered the rear by about 5 mm, raised the front by about 2.5 mm. Almost flattened the ride, 7-8 mm minus from the rake of 10-12 mm I had. Much better, the rear is not really floaty anymore.

(1 full turn of the front spring perch is 2.5 mm (corrected) at the wheels, if my measurements are correct)

At +2 clicks harder from baseline all around it's still very comfortable and fluid. Will try stiffer settings and see which I like best.

Still need to figure out the best alignment settings, too. The rear lets go under throttle easier than I'd like to. Rained today and it was obvious again.

Last edited by x233; 05-05-2020 at 05:37 PM..
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      04-28-2020, 03:01 PM   #7
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Quote:
Originally Posted by x233 View Post
Lowered the rear by about 5 mm, raised the front by about 2.5 mm. Almost flattened the ride, 7-8 mm minus from the rake of 10-12 mm I had. Much better, the rear is not really floaty anymore.

(1 full turn of the front spring perch is 3 mm at the wheels, if my measurements are correct)

At +2 clicks harder from baseline all around it's still very comfortable and fluid. Will try stiffer settings and see which I like best.

Still need to figure out the best alignment settings, too. The rear lets go under throttle easier than I'd like to. Rained today and it was obvious again.
Try toe out at the front and toe in at the rear .
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      04-29-2020, 08:18 PM   #8
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Quote:
Originally Posted by dacian View Post
Try toe out at the front and toe in at the rear .
Must be a sad state of affairs if you try to emulate the stock suspension

On a more serious note, I think I still want to go about 1 mm lower in the rear and get the rear alignment to 0.10 toe in (default is 0.08) and -1.30 camber (default is -1.40 / it's certainly suboptimal again that I changed the front and rear heights again).

Also, I don't think it's just the alignment. As I get the rear a bit stiffer the traction gets better so I think it's also the shock settings that might be too loose at +2 harder than the default 10.

Also, I still can sense the brakes are still biased towards the front a bit, so lowering the rear a bit further is going to help that.

When I changed the front/rear heights soon after that I also went to a bit harder shock settings... +4 front and +3 rear (harder than the default 10). It's OK. I've got gotten used to it but the car is more tight overall and, therefore, not as playful as with softer settings. It does help traction, though, and braking, too, especially on bumpy roads now that the chassis is more composed and settles quicker.

The steering is OK in comfort mode with these settings, and feels just right with the fronts 1 click harder than the rears, but I'd have to go to the gym to be able to steer in sport plus now, honestly (super tight) If you soften the rear you also loosen it, there's less traction, the steering gets lighter and the car gets more tail happy, that would be the setting if your intention was to go sideways much of the time.

The thing with the new suspension is that as you go stiffer/harder with the shocks rebound settings it doesn't really get crashy it just gets tighter and tighter, both the chassis overall and steering. The harder front makes the steering sharper, the harder rear makes it tighter.

Also, because part of my everyday driving is on some imperfect/crappy roads I have to use a setting that's not too sloppy while at the same time making sure the fronts or rears don't skip on bumpy surfaces while braking or accelerating.
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      05-12-2020, 09:34 PM   #9
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Update: I have been able to find a workable setup with these coilovers. Not necessarily a perfect one or the only one possible but the one that suits my handling requirements and looks.

My final drop is 30-31 mm in the front and about 27 mm in the rear, rebound set to +5 harder than the factory default in the front and +3 harder in the rear. This seems to work best of all of the combinations I’ve tried in the past month.

Not sure about the alignment, and will have to re-align this week, but last time before I made a zillion height adjustments the front had stock camber and 0.03 symmetrical toe-in, the rear had -1.35 camber and 0.09 symmetrical toe-in. (pretty sure it’s off now, but I’m only going to do minor adjustments and straighten the steering wheel).

_________________________

If I had to do it all again, I’d do the following:

I’d re-index all the bolts and nuts just like BMW suggests, to be on the safe side. I’d also use new front and rear top mounts, gaskets and rear spring seats.

As for the height adjustment:

I’d start with the rear, set the rear 10 turns of the spring perch from 0 which would be about 10 mm on the perch (that’s the minimum recommended by Sachs and which I exceed on my setup) and about 20 mm drop in the rear.

Only then would I start working on the front. As it comes from the factory the front is lower than it needs to be and I’d work it gradually until I got about a flat ride, maybe about 2 mm more drop in the front.

Let the car sit overnight, do an initial alignment to get the factory values.

Then drive it back and forth a couple of days just because, probably set the rebound a couple of clicks harder right away since the settings it comes with from the factory are too sloppy for my taste.

Then I would switch off the aids and start taking turns, start pushing it to see how the car handles, and would incrementally either lower or raise the front (without messing with the rear)
until it resolved the understeer/oversteer.

If the drop in the front was getting 4 mm more than the rear would I start stiffening the rebound of the fronts vs the rears to remove understeer.

If at that point I’d get either oversteer or understeer I’d come back to lowering/raising the front by 1/6 of a turn of the spring perch to make it just right balance-wise.

Do the final wheel alignment.

_________________________

In my experience getting the front drop more had a negative impact on traction, not just in turns but in straight line also. It’s not noticeable at 2 mm difference but at 5 mm it already is.

Having a flat ride and equal rebound settings, say +3 front and rear, gets you excellent traction, even with all the nannies off you can literally floor it and it would just grip and go. The problem, though, is that with the flat ride and equal rebound settings you get a lot of understeer, especially in fast tight turns. Hence, I had to both drop the front a bit and stiffen the front vs the rear. Only stiffening the rebound of the front shocks, even +3 vs the rears, didn’t completely eliminate understeer at corner entry in fast turns, especially obvious on wet pavement.

Having the front drop more than a few of mm I noticed the braking performance wasn’t as great as on the stock car as too much weight was moving toward the front off the rear. At about 4 mm difference on my setup I find it acceptable, though. Same thing with too soft shock settings.

I think my setup is probably a bit lower that it should be, some 5-7 mm lower, and there could be rubbing issues with winter tires (PA4) in the front which are bit wider and taller but I’ll worry about it if that happens. I don’t think the front bottoms out but I am afraid the rear is close to the bump stops and I don’t know how it’ll behave if I load it with adult passengers and some bags. With just me and 2 kids it’s fine, though.

I was honestly getting frustrated trying to get the handling I liked, with how long it took me. So, even though I realize it probably should be a bit higher than my setup I am just not ready to do it all over again. For now, I would just like to enjoy what I’ve got.

As it is, it’s tight, noticeably tighter than stock, but also nimbler, sharp as a scalpel, there’s hardly any understeer at all while the rear is reasonably planted, more so than the stock, I can push it hard without losing my rear, the ride is stiffer than the stock but not crashy. My kids sitting in the back do complain, though, that it’s more bouncy on back roads but that could also be because I am now pushing it a lot harder.
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      05-17-2020, 05:06 AM   #10
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Quote:
Originally Posted by dacian View Post
Try toe out at the front and toe in at the rear .
In theory, yes, but in practice there's only so much rear toe in you want to run... I don't think it should be more than 0.10 symmetrically (or 0.20 total). imho.

Interestingly, it's more rear vs front height that has an effect on that than the alignment settings, as well as rear rebound settings. Stiffer rear rebound settings actually make the rear more planted, too, up to a point at least where it's too tight and begins skipping.
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      07-13-2020, 08:35 PM   #11
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Update:

7,000 km and 3 months after install I am done with these. Swapped out for M Performance coilovers. Long story short: not really worth it, and not really suited for M2C.
It will get you around but better forget it.

In detail:

1) There are no recommended (height and rebound) settings for M2C anywhere to be found in the manual. You are completely on your own to try whatever you think might work.

2) I really don’t think it’s properly suited for M2C. Obviously, it was designed for M3/M4 (and I don’t even know if they work on those cars) and M2 and M2C were added to certificate as an afterthought. Obviously, no appropriate testing was done.

3) You simply cannot adjust the front height to match the rear. You can get a workable setup with a mild/moderate front rake but you can’t match the front height. The highest the front will go when settled in my case is 30 mm driver’s side and 28 mm passenger’s side – that’s when you have no more thread on the shock body to raise the spring anymore. Also, the front springs apparently sag over time because I kept going up during these 3 months but was still getting the same stupid 28/30 mm drop. With that front you can get 23-25 mm drop in the rear that will work, kind of.

You can raise the rear as high as you want but it doesn’t matter because you can’t raise the front to match. You can get the rear lower (say 28 mm drop) but you really don’t want to (see below).

4) The rub. As I was using and pushing the car more (no track), and it wasn’t obvious the first couple of weeks, just aggressive driving, I was getting a rub both in the front and the rear. I was getting a rub at 28/30 mm drop in the front and 23 mm in the rear (and you can’t go higher than that if you need a balanced car). I was rubbing the plastic of the inside wheel wells both front and rear when driving aggressively, especially on bumpy/undulating roads, or loading the car with 2 passengers and/or bags.

Stiffening up the shocks didn’t help that much. Only was too bumpy. That’s on used summer tires. When I put in a new set of rear tires it became too much. I was afraid of shredding the tires against some protruding parts in the wheel wells. Using winter tires is out of the question, would definitely rub all the time.

5) I still do think the springs are too soft. And underdamped. There’s too much travel. Add to that the fact that when a driver is in the suspension sags further 3 mm, don’t know how much if completely loaded.

I was eventually running the shocks 4 open (out 20) to minimize the excessive wheel travel and rub (and raised as much as I could) but that still didn’t resolve the problem completely. While at these “stiff” settings driving on bad roads was a bit too sketchy.

6) Didn’t like how the car handled at hight speed (200 km/hr and above). Felt a bit floaty on perfect roads compared to the stock, no matter the shock settings.

7) Didn’t like how the front was damped. I was missing some grip of the front tires (vs stock) when braking hard on bad pavement or “ripples”. No matter the shock settings couldn't get it quite right, it would still skip.

7) Eventually, a ball joint of my driver’s side front LCA went bust (at 26,000 km, and 7,000 post coilovers install).

_________________________

I probably should regret getting these but if I hadn’t I wouldn’t have learned that much about tweaking my car’s handling

Hopefully, that experience will help me get the M Performance coilovers right. But out of the box, all default settings, the MP coilovers feel like an improvement.

Last edited by x233; 07-13-2020 at 08:59 PM..
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      09-29-2021, 03:39 PM   #12
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Just a note, late note, the right way to setup coilovers is to do corner balance.
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      09-29-2021, 04:15 PM   #13
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Quote:
Originally Posted by Mollyran View Post
Just a note, late note, the right way to setup coilovers is to do corner balance.
You are correct. No objection to your statement, although some brands just give you exact measurements of height adjustment and loads to be placed in the cabin to get the desired result, e.g., M Performance coilovers so the shop doesn't have to corner balance.

The problem with these, though, is that you can't raise the front high enough to prevent rubbing no matter the rear height and no matter the rebound adjustment.
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      09-30-2021, 04:50 AM   #14
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I am about to install coilovers on my M240i and these were on my list, really appreciate your review about them. They are on sale now and for a quality Coilovers the price is really good. After reading your review I am not sure about them (not worried about rubbing since I ride on "18) but my thought is that I can always take them to suspension specialist for rebuild and maybe install new springs to come with the new valving. I also thought about M Performance set but I am not sure about daily comfort since the sport suspension I have not that good in the comfort zone.
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      09-30-2021, 06:58 AM   #15
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Quote:
Originally Posted by Mollyran View Post
I am about to install coilovers on my M240i and these were on my list, really appreciate your review about them. They are on sale now and for a quality Coilovers the price is really good. After reading your review I am not sure about them (not worried about rubbing since I ride on "18) but my thought is that I can always take them to suspension specialist for rebuild and maybe install new springs to come with the new valving. I also thought about M Performance set but I am not sure about daily comfort since the sport suspension I have not that good in the comfort zone.
No idea how they would work on M240i. I have a M235i and it runs on KW DDC coilover kit, a decent upgrade for street use. They have to be rather low to be properly planted, this is sometimes a problem in winter and climbing up some drives. But that car is a completely different, anyway.

As for the Sachs coilovers, I am not a mechanic and I am ready to admit that maybe I just wasn't smart enough, patient enough, or technical enough to get them right. I kind of don't think so but it's still a possibility.

I saw them fitted on F80 M3 and F87 OG M2 (but not M2C.) and heard people say they were happy with them. My experience was different. Was pretty much on my own tuning them after install and after a while I gave up because I just wanted to enjoy my car rather than spend the whole summer trying to get what didn't seem likely to happen anyway.

M Performance Kit was a breeze after that.
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      09-30-2021, 08:18 AM   #16
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Aside from the perfect fitment, how do you compare the Sachs to the M performance kit?
I can't go very low since on my way from home I have to go over 15 speed bumps each time, some are pretty high, so looking for about 20mm max and there's not a lot of option for that.
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      09-30-2021, 05:55 PM   #17
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Quote:
Originally Posted by Mollyran View Post
Aside from the perfect fitment, how do you compare the Sachs to the M performance kit?
I can't go very low since on my way from home I have to go over 15 speed bumps each time, some are pretty high, so looking for about 20mm max and there's not a lot of option for that.
I am mostly very happy with the M performance kit. It's not perfect but it's way way better.

I miss the ease/convenience of adjustability, by that I mean how easy it is to reach knobs, turn them, how solid they are, etc., of kits such as Sachs, Bilstein, AST, etc. You have to raise the car, take off wheels, etc. and the KW adjusters are flimsy. It's fine if you drive in dry warm climate but once it's cold, begins to rain and there's dirt they become a problem (unlike Sachs, Bilstein, AST, etc). Working on rear compression is a PITA, and I had one compression knob seize in the front and one fell off completely after winter driving, rain, dust, dirt, a year after install. So it depends on where you drive.

Otherwise, they are a very good choice.

Their settings are spot on for daily use as delivered. It's my daily. They give you just the amount of lowering that's reasonable, perfect indeed, and not more, which is fine because they don't allow you to go stupid low. I don't track but I do abuse my car, long trips, mountains, winter driving, really high speed, back roads, etc. They fit the bill for what I do with my car. Handling is great. Traction is great. Comfort is improved. Balance and feel of the car is great. Fine-tuning while not exactly convenient is not too complicated. Good thing to have separate rebound and compression adjustability. All the settings I use for my various conditions and tires are actually within 1 click from the factory default setup.

Longevity... I've had them for 15 months, use the car every day, including in inclement weather (which normally takes a toll on anything you run). That's good in my book.
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