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      09-27-2023, 06:58 PM   #1
Scandinavian_Flick
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E92 M3 Ohlins Road and Track, Swift Springs, Ground Control Camber Plates

Almost 2 years ago when I first got my M3 I said that my first 'big mod' would probably be a big brake kit to fix the less-than-ideal single pistons that BMW decided to fit to these cars from the factory. However, a little less than a year ago I fell victim to a fate as old as time (maybe): "Electronic Damping Control Malfunction".

I was able to narrow down the issue to a fried control module, and after dozens of failed attempts to re-flash and initialize the EDC module, I gave up and kept driving the car pretending that I never had EDC in the first place. Eventually I got tired of this and so instead of doing the rational thing and replacing the EDC module with a new one and coding it into the car for a lot less money, I convinced myself that it made more sense to abandon the EDC entirely and move to a more dedicated coilover setup with some clicky knobs to control damping instead of a computer and weird electron thingys.

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I decided to go with a setup based on the Ohlins DFV Road and Track dampers, however with stiffer springs in order to accommodate wider, stickier tires in the future. I figured that I would end up with wider wheels and tires sooner than the dampers would need their first rebuild, so I opted to go for the revalve now and just deal with the stiffer ride for the meantime even if I dont need it yet.

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The spring rates to use were a point of deliberation for a few weeks, and after numerous calculations for wheel rate, travel, grip, etc. I decided to go with 500 pound front springs and 800 pound rear springs. I later found out that these are also the exact same spring rates that the M3 GTS uses, which made me feel even more comfortable with that choice. I think that with the range of damping adjustment on the Ohlins, these rates will provide a nice middle zone between street car/mountain road driving and track-ready performance depending on where I set damping. To accommodate these spring rate changes, I ordered the dampers via Precision Sport Inc. in Sonoma, CA, where Jayme was a huge help in the ordering process. PSI revalved the dampers according to the spring rates I'll be using.

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Lastly, I ordered a set of Ground Control Street camber plates to allow for more camber adjustment. I have the alignment pins on the stock shocks removed already and camber maxed out as far as it can go, and I still wear the outside of the front tires way sooner than the rest of the tread even with my mix of 80% daily driving. I know for certain that without more camber, I would be absolutely melting my front tires with the added performance of the Ohlins.

PSI also surprised me by including a printout of my shock dyno graphs, which I didn't even ask for - Shoutout to fantastic attention to detail. You can see that the shocks are relatively digressive and changes in the clicks translate to real distinguishable changes in damping force. You can also see Ohlins' DFV system at work, with adjustments having a small change in compression damping force as well.

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I can't wait to get these shocks on the car; planning to do so this coming weekend along with a stud conversion and some spacers so that (hopefully) my fitment doesn't look goofy when the car gets lowered a little. - Check back in after this weekend for another update of the install process and some first impressions! Cheers.
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Last edited by Scandinavian_Flick; 10-16-2023 at 08:51 PM..
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      09-27-2023, 08:32 PM   #2
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I run stock camber (pins still installed) and have no problems. Maybe you are too afraid of exposing the "chicken strips" on the outside shoulders of your front tires. Some cowards call this "cording" and "unsafe." I think they're on the payroll of big Camber Plate.

Seriously though, excited to see the install! Great photos.
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      10-26-2023, 07:43 PM   #3
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Did you get a chance to install these? Curious how you like them! Oh, and pics

I'm about to pull the trigger on R&T myself but was gonna stick with the regular ohlins springs? didn't know there were options?
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      10-30-2023, 08:51 PM   #4
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Update!

Been a while since my first post, but wanted to update with some photos of the install and some impressions.

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The install was so simple. I thought I would be spending a couple days on this but managed to install both front struts and their respective camber plates in about 2 hours, even with all the time I (rather obsessively) spent measuring and adjusting things to the exact 10th of a millimeter.......just to change it later when I went to adjust the ride height lol. The Ohlins install guide is pretty self explanatory, spare for a few items of confusion such as how they label the rear spring perch adjuster as the preload adjuster...which it isn't. Also helped that my relatively low mileage California car doesn't have a single spot of corrosion on the bottom, thus no stuck bolts. Sorry to all the east coasters.

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....Anyway, Once I waited for the suspension to settle a bit over the first few days I went back to adjust the ride height. Super simple to do in the front, a little harder in the rear. Making adjustments in the front probably takes 10 minutes a side versus about 20 in the rear. Eventually got the ride height just where I want it. I dont have scales to corner balance the car, but it's not setting lap records in its current state anyway, and it's definitely close enough for the street.

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I still have a few things to work out with the suspension that I've been lazy to do. First, I have adjustable end links in the front, but they're too long, so I think they might be contacting on the camber arm - need to order some. Second, the rear damping adjuster situation is complicated. I need to get some extensions, because at the moment I have no trunk carpet still lol. I have a friend with a 135i also running Ohlins, and his rear dampers have a little whip knob to extend the adjuster, which is great for keeping the stock carpet, but the whip obscures the damping clicks in the same way that socket extensions obscure torque values, so you cant actually tell how much you're adjusting – infuriating. Going to have to figure out a better solution for that.

Minor issues aside, these dampers are fantastic. I was worried that the stiffer springs I decided to use were going to be too much, and they definitely aren't. I've found that 16 clicks is just about the sweet spot for comfort, softer than that and they tend to stop controlling the spring and the ride gets a little bouncy. I think that at this setting, the car rides comparably comfortable to the EDC in its middle setting. Turn the dampers stiffer and the ride is still compliant, but very confidence inspiring. I haven't had the chance to take these on track yet, but driving spiritedly on some quiet roads, the car remains shockingly planted over rough surfaces and cornering grip is greatly increased. The stagger between the front and rear spring rates is great for the oversteer/understeer balance too, the rear is lively without wanting to kill you, and the front will still push just a tiny bit, which is easily tamed with some adjustment via the camber plates.

Wheel fitment is also pretty good thanks to the studs and spacers I installed concurrently. Ideally I'd get some wider wheels to fill out the arches even better, and more importantly run a square setup with wider tires, but that will come later. All-in-all, the car is fantastic and I can't wait to get it on track, hopefully by the end of the year. I can make another post then with some more feedback too.
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      10-30-2023, 08:58 PM   #5
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Quote:
Originally Posted by Thumbie View Post
Did you get a chance to install these? Curious how you like them! Oh, and pics

I'm about to pull the trigger on R&T myself but was gonna stick with the regular ohlins springs? didn't know there were options?
Just uploaded some feedback, but feel free to ask me any more specific questions you might have!

The stiffer springs aren't really an 'option' per-se. I had the dampers revalved by Performance Shock to accommodate the change. Ohlins can actually do this in-house as well, however its more expensive and the lead times were apparently pretty long when I ordered mine. Any Ohlins dealer can revalve the dampers to accommodate pretty much any spring rate.

Depending on your application, the regular Ohlins springs might be great. A lot of people say they're too soft, but it just depends on your use case. If you plan on taking your car to the track ~5 times a year like I do, then yeah they might be too soft. But, if you're driving your car only on the street, the stock springs are definitely capable of handling the average canyon road and will maintain better ride comfort. I actually think that the 'base' Ohlins with the regular springs rides more comfortably than stock.
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      10-31-2023, 03:34 PM   #6
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Great feedback, and the car looks amazing

i'm only tracking 1-2 times per year so I think the ohlins springs are fine. Can always swap and revalve later

Also, regarding your dilema with access to rear damper adjustment. Check out post #4 of this thread below. Guy basically found some large plugs and cut access holes in the liner.

https://www.m3post.com/forums/showthread.php?t=2039819
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      10-31-2023, 07:15 PM   #7
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For rear damper access I just cut square flap in the trunk carpet. It's stiff enough that it will stay closed and is virtually invisible when it's closed. No need fancy extenders (expensive) or holes with plugs.
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      10-31-2023, 09:45 PM   #8
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Any particular reason you went custom instead of the Ohlins dedicated track setup? Just based on your rate calculation, or for a softer setup than the dedicated track setup? I’ve been torn between R&D and dedicated track options. Maybe this is the sweet spot..
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      11-02-2023, 09:28 AM   #9
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Quote:
Originally Posted by Redd View Post
For rear damper access I just cut square flap in the trunk carpet. It's stiff enough that it will stay closed and is virtually invisible when it's closed. No need fancy extenders (expensive) or holes with plugs.
I installed R&T on my E90 M3 2 months ago and it's the best mod I've done to the car in my 4 years of ownership.

Based on some pics I saw in an Ohlins thread, I used a hole saw and cut out circles in the felt above where the dampers sit. I think it's a good solution and avoids the vague feeling whip extensions.

Enjoy the new setup!
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      11-08-2023, 06:43 PM   #10
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Quote:
Originally Posted by askjeeves View Post
Any particular reason you went custom instead of the Ohlins dedicated track setup? Just based on your rate calculation, or for a softer setup than the dedicated track setup? I’ve been torn between R&D and dedicated track options. Maybe this is the sweet spot..
Great question. The dedicated track uses springs that are about 200lbs stiffer on each axle, which I think would have just been too much for my application. 700/1000lbs works great on track cars, especially with a square setup of 200tw tires, but is certainly going to be less compliant. My car has to occupy daily driver duties as well as weekend drives and track days, with track time taking up probably only a small percent of my driving.

The dedicated track setup also uses the Vorschlag camber plates, which are certainly a quality product, but they use a race bearing which is unsealed and offers no compliance. Great for a track car, but for a car that sees more road debris and needs to remain comfortable, I think that the GC street plates are better because of the polyurethane bushings which are less prone to premature wear and have less NVH.

So at the stage my car is at, this is the sweet spot for me. I also think that if you were at the point where you're raising the spring rates to that ~700/1000 range, you're probably better suited with a more advanced damper like something with independent rebound and compression such as MCS 2W or Ohlins TTX.
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      12-15-2023, 12:06 PM   #11
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Quote:
Originally Posted by Scandinavian_Flick View Post
Great question. The dedicated track uses springs that are about 200lbs stiffer on each axle, which I think would have just been too much for my application. 700/1000lbs works great on track cars, especially with a square setup of 200tw tires, but is certainly going to be less compliant. My car has to occupy daily driver duties as well as weekend drives and track days, with track time taking up probably only a small percent of my driving.

The dedicated track setup also uses the Vorschlag camber plates, which are certainly a quality product, but they use a race bearing which is unsealed and offers no compliance. Great for a track car, but for a car that sees more road debris and needs to remain comfortable, I think that the GC street plates are better because of the polyurethane bushings which are less prone to premature wear and have less NVH.

So at the stage my car is at, this is the sweet spot for me. I also think that if you were at the point where you're raising the spring rates to that ~700/1000 range, you're probably better suited with a more advanced damper like something with independent rebound and compression such as MCS 2W or Ohlins TTX.
This is a good evaluation but I would point out that the Dedicated system is tuned for a use case of someone who prefers a track-focused package with minimal setup and less complications associated with a multi-way adjuster. There is a sizable market there.

Additionally, the durability of the DFV damper is very high, which is also conducive to that same user wanting to build a lower maintence track car.

But yes, to your point, a multi-way adjustable motorsport damper is more conducive for competition events and an end user willing to accept trade offs associated with a motorsport damper. But it's certainly vital the end user understands how to make the adjustments to a multi way adjustable damper to gain the benefits and not create more issues.

Hope this helps.
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      12-17-2023, 02:19 PM   #12
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Confused as why you not have gone with Ohlins dedicated if you wanted stiffer spring rates so that you have calving that matches stiffer springs? Maybe they are no longer available and I’m not up to speed…..

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      12-17-2023, 04:10 PM   #13
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Based on your spring rates of F/R 500/800 lbf/in I’m surprised the dampers required a revalving. The R&T should be capable of handing changes in spring rates of +/- 200-300 lbf/in easily relative to R&T standard kit rates . Also if PSI is offering a Track day setup then the dampers should have already been properly revalved, rather than have standard e92 m3 R&T damper valving. If you had purchased the 3DM’s track day R&T setup they’d come approximately valved for your rates at no extra charge and then they also include one future revalving for free.

I’ve used the R&T (DVF) dampers on my R56 Mini CS for > 10 years and I’ve always felt/referred to them as 1-way adjustable but so many people have told me they are 2-way due to DFV. Well looking at your damper dyno plots it shows how little overall C adjustment you get for a change in R adjustment. Most dampers, except for high end race dampers such as Ohlins TTX, MCS Remote, JRZ Race, etc., show crosstalk between R & C adjustment and that’s basically what the R&T act like based on your plots - a typical 1-way R adjustable damper. Also, in typical cases to solve a handling issue, you’ll be adjusting say C up, R down, something even a damper like a “2-way” R&T cannot do.

Last edited by M3SQRD; 12-17-2023 at 04:27 PM..
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