Motion Control Suspension 2-way review

[Richbot]

I've posted a few other notes and impressions in the autocross thread in the track forum but I figured I'd put it all here for searchability's sake.

Back in March, I ordered a set of MCS ( http://www.motioncontrolsuspension.com ) 2-way remote reservoir dampers for my E90 M3. They arrived in very early May or very late April ahead of the promised lead time, and I've finally got them on the car now. I ordered them configured for SCCA Stock-class autocross competition, which requires the use no more than two external adjustments, stock ride height, and use of stock springs and strut mounts, which means they were machined with a shoulder and a welded ring to accept the stock spring perches. This is similar in concept to what JRZ made for the VS Motorsports T2 E92, and in fact I ordered this MCS setup through VS Motorsports in the Chicago area, which was a great experience. Top notch customer service and good pricing.

First of all, I can't say enough about how responsive and helpful Lex at MCS has been in working through this and getting them on the car. The stock spring perches do fit, but when I was unable to get them on straight with the tools in my garage, I just shipped the whole thing with the stock springs and mounts and everything back to MCS, where they pressed the perches on, reassembled everything, and I was able to just install everything as an assembly. They really were more of a press fit, but that's good, that means they aren't going anywhere. Service after the sale is one of the most important parts of buying one of these pimp shock setups and MCS delivers.

I've had the shocks on the car for a few weeks but just got the struts on the car of yesterday morning, and I will have an autocross in a few weeks to really try them out. Having already had on event on the car with just the rears, the adjustment range and performance is really amazing. Rebound goes from softer than stock to waaay stiffer than stock to the point where you can pack the car down on the bumpstops if you want to. Compression is similarly very wide-ranging and has a big impact on transient response, I'm still playing with it.

Behavior over big hits and mid-corner bumps is where the car is really transformed. You really, really have to try to upset the car now, and the skating over mid-corner bumps that was present with the stock dampers is just gone. Throttle oversteer is still available whenever you want, but you don't need to tiptoe over bumps like the stock setup requires.

The other really neat part of these things is the nitrogen pressure adjustability, which is a feature of most remote reservoir dampers. I've got them set at 250psig right now and the car seems to really like the extra "spring rate" from the nitrogen lift, which makes sense with my car limited by the stock spring rates. Interesting side note, With about 75 psig in the canisters, the car rides about 1/4" lower than with the pressure set at 250. I'm happy to report that the canisters appear to hold pressure just fine as well, I'm probably losing more pressure just checking the pressure than is actually bleeding down.

I'm running 295/30-18 and 315/30-18 Hoosier A6's and preventing rollover is key when you're stuck with near-stock camber (-1.4 ish with the pins pulled) running bigass tires, so the added roll resistance should be a big help, especially in the front, where I might be able to soften the front bar while maintaining roll stiffness, which will help with mid-corner balance. Lots of fun stuff to play with. The tire wear will tell the tale at the next event. Actually picked up about 1/8" of additional tire clearance to the strut with this setup, which is nice to have. Might be room for 305's on the front now.

For the street, I've settled on about 100psi in the canisters for the slightly lower ride height, and 3 clicks from soft on the rebound all around, with 2 clicks of compression in front and 4 in the rear. This seems to keep the control over big hits effective without inducing any head toss over rough concrete. Turned all the way down, the car feels underdamped, but it might be ideal for a long freeway trip as it rides pretty damn nice with them turned down, with the only harshness coming from the relatively stiff M bushings. There's a noticeable difference between each adjustment point, which I'm very surprised by as I was expecting to need 3-4 clicks to notice a difference with all the soft bushings, heavy car, floppy springs I have going on.

The MCS setup in total weighs about 8 lbs more than stock. This is partly because of the remote reservoirs and hoses and partly because the struts use a steel body instead of aluminum. Most of extra weight is in the struts themselves. The shocks are within half a pound of stock including the canister.

Mounting the canisters was probably the most difficult part of the install except for getting the spring perches on the struts. I ended up routing the rears through a notch cut in the trunk vents on each side, didn't even need to cut the fender liner, and zip-tied the canisters to the carpet which I'm required to retain in Stock class. It was my best solution for ease of adjustability for both compression and nitrogen pressure and keeping them out of the way of cargo with the length I had available. The fronts are routed up along the brake line with some cut fuel hose protecting them from abrasion against the brake line bracket, and the canisters were placed by the windshield drains. This is really more of a friction fit, using some leftover racecar fuel cell foam to hold it in place. I didn't want to have to cut and re-ziptie the canisters every time I want to adjust pressure, and this still allows easy access to the compression adjuster if needed.

Will report back with impressions after I've competed on them a few times and have a better idea what I like for autocross settings. I have a feeling I won't be far off my street settings.

tl;dr: Highly recommend MCS for your E9x Pimp Damper needs. See below for out-of-focus photos

[signes]

Great write-up, nice setup. Keep hearing great things about MCS. Curious what else (if anything) you considered before settling on this setup?

[Richbot]

I talked to Anze (penske internals), Guy Ankeny was working with me to try to get a Quantum setup done for e9x, and considered a 2-way version of the JRZ setup for stock springs. MCS was price competitive and could meet my timeframe, and reputation of the players was good along with the USA based angle that has worked out well on the customer service side of things, though that's not to say that the others don't provide high quality service.

[VSmotorsports]

Great Review Rich glad you like them so far! We had the same thing happen for us with the car lifting when adding nitrogen to the JRZ's. Got to love the 4x4 look. We ran about 250psi as well during our race. Couldn't agree more about the customer service. lex is top notch and when you are in a bind he is there to help.

We actually just picked up a set of triple adjustables for our car and have the first race this weekend.

[Richbot]

Had a chance to get these dialed in over the past few events, and here are the settings I've settled on for autocross Balance is very good now, and any understeer I experience is a result of overdriving the car. Other relevant parts on the car for reference are camber pins are pulled in front, turner endlinks and RD Sport front bar on full stiff, and 295/30-18 and 315/30-18 hoosier A6's.

Front
Bump: 10 clicks from full soft
Rebound: 8 clicks from full soft
N2: 125 psig cold

Rear
Bump: 7 clicks from full soft (been using this adjustment to tune on-throttle behavior)
Rebound: 8 clicks from full soft
N2: 250 psig cold

What I found with the 200+psi pressures in front was that the ride height penalty was not worth the extra effective spring rate, and I was giving up front bite due to ride height and loss of static camber. With the struts at 250 psi I was at -1 degree, at 125 psi I'm at -1.4 degrees. Would be nice to have the extra N2 pressure without the ride height penalty but that's life, can't change the spring perch location in Stock class.

[flipm3]

Thanks for sharing the data and driving impressions.

I can't wait to pick up my own set of MCS dampers in the future!

[sc_tr0jan_m3]

love my mcs setup. so happy with it on and off the track.

[klammer]

Any more impressions on these??? Look pretty nice and seems like quite the upgrade.

[Richbot]

I drove a stock M3 recently and the difference is pretty damn obvious. Mine is better.

Nitrogen pressure has been rock solid, set-it-and-forget-it. I've got close to 5,000 street miles on these and dozens of autocross runs and the pressure I set two weeks ago is consistently the same when I check it the next time. This is a good thing, as I've had friends with Motons in the past that bled down after a couple weeks.

[flipm3]

That's great to hear!

I know your rears are threaded, but can you send the front back in to MCS to convert to a coilover setup?

If so, would they require new valving to work with conservative spring rates?

[Richbot]

They should work with the current valving up to some pretty stiff spring rates. I'm overdamping the car bigtime with the settings I'm using now to compensate for the soft stock springs, and am only halfway through the adjustment range. As for converting the fronts to coilovers, they might have to change the strut body or if I wanted to do it at home I could press the stock spring perches off the strut bodies and use a sleeveover kit. And of course they sell them threaded, mine was a special case

[klammer]

Am kind of really wanting these

[E92inSG]

anymore pics on how the front reservoirs were mounted?