[NiNeTyOne]

Eibach Sport spring and FSD's are installed. I used the European Eibach kit (E10-20-014-10-22) that is not brought into North America for the e91 X-Drive Sportwagon, ordering it from Germany last week. Surprisingly, the alignment is still quite good after the install. I've already done a lot of bushings with poly, so things stayed pretty well in alignment. I'll still have it touched up in a couple weeks once it's settled.

I went with FSD's because I wanted the car stiffer in corners and at speed, but didn't want a monotube design after putting Ohlins suspension on the last car (it kinda spoiled me). Monotubes are great with less varied road conditions, like Japan or Europe, but Seattle has been a non-stop construction site for 10 years now. Our roads are an absolute nightmare mix of billiard table smooth asphalt to bombed out Beruit, circa 1986. Even NYC was better when I lived there.

My rear strut bushings were replaced with Strongflex yellow, along with all the spring pads from the dealer. During install I made a point of loosening the lower CA bolts when doing the install to take some of the load of the bushings. This made life a lot easier. Everything was re-torqued at the new ride height. The front bushings would have been under some tension had I not done this.

Initial impressions:

Crisper turn in and better front grip with the added camber from the drop, noticeably reduced body roll (although a rear bar is still in order on the e91).

Improved steering feel, much more neutral through the corners (less tendency to under steer (again with the drop in the front I expected as much)), and better feedback into the driver's hands on the edge of grip (still just a touch of under steer on the limit :/ ).

All that said, it's definitely a bit looser with the nose dropped about 30mm, and I can drive the car into and through corners a fair bit quicker than I could before (I'm gunna keep ranting on about all the horrible stock understeer).

The rear of the car is almost identical to the OE springs, with just a tiny additional drop.

The dampers are a great mix of firm but controlled damping in corners (providing a very firm, taught feel when the car takes a set into the corner) while providing pretty good road manners over bumps, pavement transitions and expansion joints. No bomb craters yet, but overall they do the job, and do it well.

The car does still float over rises when the roadway falls away very quickly, but I think they will get better as they wear in and settle. Rebound always seems to improve on new shocks after about 4-500 miles. This is the one area where Koni could have made these better. But they are far from floaty. I have tracked a LOT over the years and driven cars with ridiculous suspension so take this with a grain of salt.

The car brakes MUCH better & rear squat under acceleration is reduced by a fair margin.

Overall it's MUCH quieter. I am going to guess improved damping reduces road noise pretty significantly, as I have the same tires on the car, but I can't say for sure. It could also be related to less wind noise from lowering the front of the car. With over 1-1/4" front drop the car presents much less to the wind.

They are not as good as the Ohlins/Eibach's on the old car, but they are also less than 1/5 the price. They are FAR better than a set of H&R coilovers I had some time ago, I'm glad I went this direction for the family grocery getter.

The combination of FSD and Eibach seems VERY well matched. They could use a touch more low frequency rebound, which would match well with a slight increase in the spring rate, but that might make them less friendly for the less demanding daily driver.

Curb and speed bump clearance is good, but I'll need to be a bit more careful than I was with the drop up front.

I'm pleased enough that I may be alright on track as well for limited use. There's not enough spring rate to run slicks though, I think would want about double the rate if I was going to do that, & I promised I wouldn't :/

Looking forward to swapping the Dunlops back over in a few days and getting the alignment touched up once it settles. I'll take a couple pics tomorrow at the BMW Centennial if it doesn't rain.

[zipstic]

What is it about your new setup that is far better than the H&R coilovers you had before?

Looking forward to the pics!

[NiNeTyOne]

The H&R's were harsh, even for a CO with progressive springs. Every bad expansion joint upset the car. Potholes were a nightmare.

On track pavement transitions upset the car more than they should have. The car felt over damped and under sprung, which tends to drive people towards more bar rather than dealing with the rate issue and making well matched dampers.

For me it's about grip and feel. They really didn't do well in either department.

The setup I just put on, while not being up to TTX levels, is a far better setup than the H&R's in my opinion.

[SM335i]

Originally Posted by NiNeTyOne

The H&R's were harsh, even for a CO with progressive springs. Every bad expansion joint upset the car. Potholes were a nightmare.

On track pavement transitions upset the car more than they should have. The car felt over damped and under sprung, which tends to drive people towards more bar rather than dealing with the rate issue and making well matched dampers.

For me it's about grip and feel. They really didn't do well in either department.

The setup I just put on, while not being up to TTX levels, is a far better setup than the H&R's in my opinion.

what setup did you put in now?

[NiNeTyOne]

Originally Posted by SM335i

what setup did you put in now?

I have a wagon, so the Eibach's I have now are different form your car.

I'm running FSD's and Eibach Pro springs.

Dedicated track car was Eiback linear racing springs on 4-way Ohlins TTX dampers. That was a $5k+ setup.

[SM335i]

Originally Posted by NiNeTyOne

I have a wagon, so the Eibach's I have now are different form your car.

I'm running FSD's and Eibach Pro springs.

Dedicated track car was Eiback linear racing springs on 4-way Ohlins TTX dampers. That was a $5k+ setup.

I always thought and read that FSDs are oem replacement, not for upgraded springs. Koni Yellows are made for lowering/aftermarket springs I believe.

[NiNeTyOne]

Originally Posted by SM335i

I always thought and read that FSDs are oem replacement, not for upgraded springs. Koni Yellows are made for lowering/aftermarket springs I believe.

Spoke directly to Eibach and Koni in Netherlands. The kit was designed to be used together and works perfectly. The only thing you need to do is tune bump stops to taste.

They actually sell this kit in Europe, complete.

[SM335i]

Originally Posted by NiNeTyOne

Spoke directly to Eibach and Koni in Netherlands. The kit was designed to be used together and works perfectly. The only thing you need to do is use shorter front bump stops as noted above.

They actually sell this kit in Europe, complete.

do you have pics? how is the xi rake after the setup? is it gone?

[NiNeTyOne]

Totally gone. Here's a couple pics of the initial settling today. It should drop a bit more in the coming days but I don't put much mileage on any more so it could take 2-3 weeks.

The front fender currently has 14mm clearance over the top of the tire, the rear has 22mm clearance. So the negative rake is totally gone.

I figure the front dropped 33mm, the rear 5mm, so far.

[Bours]

Can i see a side pic im on the edge of buying this

[rothwem]

Interesting that your rear axle hardly dropped at all--the Eibach website says that its supposed to drop 30mm front and 25mm rear.

[NiNeTyOne]

It actually dropped quite a bit in the rear. Look at the hub to fender factory heights, It dropped 25 rear and more like 35 front.

My measurements may be off by a little, as I didn't exactly locate the center on the hub, but the images were about 3 days after install, it's settled a bit more now to these numbers. It's been about 3000 miles.

[rothwem]

Originally Posted by NiNeTyOne

It actually dropped quite a bit in the rear. Look at the hub to fender factory heights, It dropped 25 rear and more like 35 front.

My measurements may be off by a little, as I didn't exactly locate the center on the hub, but the images were about 3 days after install, it's settled a bit more now to these numbers. It's been about 3000 miles.

Interesting. It looks pretty close to the stock suspension in my wagon.

[Antetokounmpo]

My front drop w/ eibachs. My rear is even lower, can't even get a finger in.

DSC_0029 by [url=https://www.flickr.com/photos/138019453@N07/]

[RMNB]

Originally Posted by Heel Toe

My front drop w/ eibachs. My rear is even lower, can't even get a finger in.

DSC_0029 by [url=https://www.flickr.com/photos/138019453@N07/]

Looks good! You have Bilstein what #?? If so, howz yur ride? Comfy, rubbing, harsh??

[Antetokounmpo]

Originally Posted by 550i Beast

Looks good! You have Bilstein what #?? If so, howz yur ride? Comfy, rubbing, harsh??

Thanks. I believe you pm'd me? I answered all those questions

[carlust33]

Originally Posted by NiNeTyOne

Spoke directly to Eibach and Koni in Netherlands. The kit was designed to be used together and works perfectly. The only thing you need to do is use shorter front bump stops as noted above.

They actually sell this kit in Europe, complete.

What front bump stops did you use - E36 M3?

[Julian2485]

Any recent pics of the car now

[2011335xi6MTMsportE90]

Would these euro springs work in my 2011 e90 335i xdrive? Or should I use the euro 330xi springs?

[NiNeTyOne]

Originally Posted by carlust33

What front bump stops did you use - E36 M3?

I have Z4m bumps, and I would not do that again, I would buy the Ohlins 650 Durometer 53mm stops front and rear, back the rear ones up with 19mm 650 Durometer, and use the yellow 10mm Ohlins ones in front, and I'd tune them with the 2.5mm Koni shims.

My guess is that I'd need two shims stacked in front, one in the rear.

The bumps I have do NOT engage early enough and when cornering hard the car needs to settle earlier.

I spent years racing so I can feel this, most drivers will never know the difference.

It's hard to tell exactly how to tune the stops right out of the box because the springs will settle over a few hundred miles. Best bet is to measure, measure, measure. I like about 20-24mm of compression from the settled height at speed (say 80-mph) before initial bump engagement and I use tapered bumps.

[mjweimer]

Originally Posted by NiNeTyOne

I have Z4m bumps, and I would not do that again, I would buy the Ohlins 650 Durometer 53mm stops front and rear, back the rear ones up with 19mm 650 Durometer, and use the yellow 10mm Ohlins ones in front, and I'd tune them with the 2.5mm Koni shims.

My guess is that I'd need two shims stacked in front, one in the rear.

The bumps I have do NOT engage early enough and when cornering hard the car needs to settle earlier.

I spent years racing so I can feel this, most drivers will never know the difference.

It's hard to tell exactly how to tune the stops right out of the box because the springs will settle over a few hundred miles. Best bet is to measure, measure, measure. I like about 20-24mm of compression from the settled height at speed (say 80-mph) before initial bump engagement and I use tapered bumps.

NiNeTyOne - great write up and thanks for sharing this info. I am planning to go the Euro Eibach/FSD route on my '11 E91xi with the upgraded shock mounts and adj. front bar links.

Couple of questions:

Do you think that the upgraded bump stops are 100% necessary? I have no track experience and will not be driving this car at 10/10ths. I know that bumpstop tuning is a fine art most overlook when building track suspensions (Steve Dinan spoke at length about this at a CCA event years ago) but not sure it matters as much for the street. Did you start out with the MZ4 front and stock rear bump stops?

In another thread you note the need for new front AND rear adj. swaybar links. Did you do something different for the rear or just the fronts?


Look forward to your comments.


MJ

[NiNeTyOne]

Front links are most important. You can shim the MZ4 bumps 5-7.5mm.