[donR]

Just wondering if the drop for the B12 kit is any more over the standard M-sport suspension?

[Nguyenhu0106]

Originally Posted by liteonled

Just wondering if the drop for the B12 kit is any more over the standard M-sport suspension?

i personally have never measured it against M sport but what i have researched i believe it is but not by alot. just look up eibach pro kit and see how it fairs against the msport

http://www.e90post.com/forums/showthread.php?t=718339

[cdgatti]

it should be 1" over non-sport and 1/2" drop from m-sport.

[Sheepy]

Originally Posted by liteonled

Just wondering if the drop for the B12 kit is any more over the standard M-sport suspension?

I have installed the Eibach pro springs but with new M sport suspension but shouldn't make a difference to ride height.
After 2 weeks front has dropped around 10mm, nearly 0.5" Rear is the same height now but after installation & a long test drive it was about 5mm higher, not too surprising as original springs had done 71k so may have been sagging a bit.

[swagon]

Originally Posted by Sheepy

I have installed the Eibach pro springs but with new M sport suspension but shouldn't make a difference to ride height.
After 2 weeks front has dropped around 10mm, nearly 0.5" Rear is the same height now but after installation & a long test drive it was about 5mm higher, not too surprising as original springs had done 71k so may have been sagging a bit.

Well, the B8 dampers that are in the B12 kit are shorter and made exactly for shorter springs.

[FZainol]

Great shocks i must say!

[simpleM3]

Where's the best/cheapest place to get these from the U.S? I found them on Ebay but it's written in German so I don't wan to chance buying them unless I can confirm exactly what I'd getting.

[Jeff@TopGearSolutions]

Originally Posted by simple335i

Where's the best/cheapest place to get these from the U.S? I found them on Ebay but it's written in German so I don't wan to chance buying them unless I can confirm exactly what I'd getting.

<----------

[MiamiM3]

Originally Posted by simple330i

Where's the best/cheapest place to get these from the U.S? I found them on Ebay but it's written in German so I don't wan to chance buying them unless I can confirm exactly what I'd getting.

http://raceconsultingagency.com/i-17...FVNk7AodAUsA0w

[nydog]

Originally Posted by simple330i

Where's the best/cheapest place to get these from the U.S? I found them on Ebay but it's written in German so I don't wan to chance buying them unless I can confirm exactly what I'd getting.

Turnermotorsports

[cvc 22349a]

This sounds like a great spring/shock combo. Are the spring rates linear or progressive? I remember when the Eibach PK springs first came out for this chassis that they were progressive rate but have read that in the B12 kit they're linear rate Also, does anyone who has this suspension know if the Bilstein strut tubes are larger in diameter than oem or Koni's?

[jjellyneck]

Originally Posted by cvc 22349a

This sounds like a great spring/shock combo. Are the spring rates linear or progressive? I remember when the Eibach PK springs first came out for this chassis that they were progressive rate but have read that in the B12 kit they're linear rate Also, does anyone who has this suspension know if the Bilstein strut tubes are larger in diameter than oem or Koni's?

The B12 kit now comes with linear spring rates.

Not sure about the size of the strut tubes though.

[coolchu001]

The B12 kit is great. Handles beautifully with an upgrade sway bar.
I had this with EC7 and PSS tires and it tore up Mid-Ohio with ease. Awesome road handling.

[cdgatti]

Originally Posted by cvc 22349a

This sounds like a great spring/shock combo. Are the spring rates linear or progressive? I remember when the Eibach PK springs first came out for this chassis that they were progressive rate but have read that in the B12 kit they're linear rate Also, does anyone who has this suspension know if the Bilstein strut tubes are larger in diameter than oem or Koni's?

Yes by virtue of the monotube design, the piston diameter is much larger than stock or koni sport which are twin tube design. In the coilover world the Ohlins are also monotube design. The benefits of monotube over twin tube are well documented, things like better lateral stability, higher oil reservoir, better cooling, etc.

[ajsalida]

Originally Posted by cdgatti

Yes by virtue of the monotube design, the piston diameter is much larger than stock or koni sport which are twin tube design. In the coilover world the Ohlins are also monotube design. The benefits of monotube over twin tube are well documented, things like better lateral stability, higher oil reservoir, better cooling, etc.

This is not entirely true in the BMW e9x instance.

In order to fit a monotube into a McPherson strut design, many compromises were made. Mainly the actual shock body (full of fluid etc.) in front on a Bilstein is the thick visible "rod" at the top of the strut that you bolt the strut hat etc. to. The conventional piston rod is hidden inside the lower housing. This means the front piston diameter is much smaller than you'd think. Also the inverted configuration means there is an extra set of large seals in this design not present in non-monotube configurations. This results in extra sticktion and also air gets trapped underneath inside the lower housing. Same comments apply to Ohlins front configuration. To my knowledge it is not possible to avoid doing this given a McP strut.

Bilsteins have internal floating pistons, many Ohlins do not.

Floating piston is another piston inside the shock body, above the ordinary piston. This floating piston separates the oil and high-pressure gas reservoir. It needs to float to compensate for rod volume as the rod extends into the fluid region and offsets fluid. This is a good design to separate fluid and gas, and prevent aeration bubbles and cavitation. Some of the Ohlins do not have this floating piston and are called emulsion type, allowing gas and oil to mix. I seem to remember reading when they first came out that the R&T Ohlins for e9x were emulsion type, please correct me if I'm wrong.

Ohlins makes a ton of very expensive shocks for bikes which are double and triple adjustable, yet still emulsion type. These can be very good, even excellent shocks. It costs as much as their full coil over kit for cars to put two good Ohlins on a bike.

Just as emulsion type shocks can be made to work well without a floating piston, twin tubes can work well also. Koni sports are a good example of this, they form the basis for some pretty decent coil over kits and have the advantage of adjustability, are used extensively in amateur racing (SCCA IT-type stuff) and are at the same price point or less than a non adjustable Bilstein. Having had both types on numerous cars I am pleased with the value and quality of the Konis, and will take the adjustable rebound feature over any slight advantages or quirks the Bilstien designs may have. Presently I have Bilstiens on my truck and Koni yellows on two cars.

A true high-pressure gas monotube with IFP and double adjustable is not available in anything but a mid-high end coil over like JRZ or Moton last I looked. Penske is also up there but doesn't make e9x stuff to my knowledge. I have a Penske rear shock on one of my bikes (Blackbird). You pay easily over $1k+ for ONE good bike shock. I am not sure what the KW V3/2/1 design is.

While it is true that a IFP monotube design is theoretically superior to a twin-tube, it is all about price vs. quality, implementation, and execution. There are plenty of outstanding twin tubes, and even some not so great monotubes. I think a lot of low end KYB's are monotubes, or were, and they mostly suck. At least the last set I had weren't so hot.

You have to lay out some serious coin to get into the realm where monotubes are clearly superior to the available twin tubes designs. And then you're comparing >$5k set of coilovers to a <$3k set. At the same (low) price point, like Koni yellow vs the Bilsteins, it is a wash IMHO. Plus there are quirks to the Bilstiens in a McP strut implementation that make me at least lean towards the adjustable features on the Konis. But either one is far superior to OEM stock.

YMMV yada yada...

[cdgatti]

Thanks for that in depth discussion AJ. No doubt both Koni and Bilstein are great shocks that both work very well for our cars and most others. Either is a great upgrade over oem.

[ajsalida]

Originally Posted by cdgatti

Thanks for that in depth discussion AJ. No doubt both Koni and Bilstein are great shocks that both work very well for our cars and most others. Either is a great upgrade over oem.

Sure thing. I worked at/with a race shop that rebuilt Penskes, Konis, Ohlins etc. back in the 90's. The guy who ran it was a PhD mechanical engineer from MIT. He also made custom double adjustable bilsteins out of regular bilsteins, and from scratch. Amazing guy and I learned a lot from him. He would get calls from Chip Gannassi and folks like that.

We did R&D work for the military, on digitally-controlled active/semi-active suspensions and robotics stuff. Fun times.

[avocet]

Originally Posted by cvc 22349a

This sounds like a great spring/shock combo. Are the spring rates linear or progressive? I remember when the Eibach PK springs first came out for this chassis that they were progressive rate but have read that in the B12 kit they're linear rate Also, does anyone who has this suspension know if the Bilstein strut tubes are larger in diameter than oem or Koni's?

Oem sport vs bilstein:

[cvc 22349a]

Originally Posted by avocet

Oem sport vs bilstein:

Thanks I know the piston rod is larger. Was wondering about the strut tube diameter/ circumference

[cpie168]

Guys, if I want to save a few bucks and want to avoid dropping the car any lower than my M-Sport ride height, can I just go get a set of Bilstein B8 shocks and pair them with my M-Sport springs? Can I expect the same ride quality as the B12 Pro-Kit? Thanks guys.

[vwetish]

Originally Posted by CJ421

Drop looks fantastic.

Aggressive cornering with the non-RFT tires will be a more predictable experience. You can feel when the tires are approaching their grip limit. RFTs give no such clue.

I can't really tell. My e90 335i M Sport looks even lower than this on stock suspension.

[simpleM3]

+1...I just installed the B12s and the drop doesn't appear to look like a drop at all. Its especially noticeable in the fronts. It isn't a bad looking stance, but I was hoping for a better drop than what I'm seeing. Maybe it needs to settle a bit more. I've only had them on for a week, so time will tell, but I also can't imagine that they'll drop enough for me to see a major difference. Aside from the lack of drop, they ride really well. I haven't had the opportunity to really test out the performance and handling because I need an alignment, but the comfort and response is exactly what I was looking for.

Originally Posted by vwetish

I can't really tell. My e90 335i M Sport looks even lower than this on stock suspension.