BMW Performance Suspension Review

[nikitino25]

So I recently installed the BMW Performance Suspension kit (v2 with yellow springs) and thought I'd write up a little review for those on the fence about this kit. I probably have 50-100 miles or so on them so far and I'll have to say that overall I'm mildly disappointed with the performance. I went from stock ZSP with 18" non run-flat Michelin PSS tires to this set up and thought the difference would be much more pronounced. It is somewhat better but not that much in my opinion. The kit did come with the front sway bar and this along with the stiffer springs does make the car turn in a little bit better and body roll is somewhat reduced but not enough in my opinion. The ride around town and on smooth roads is actually very good and the turn in is crisper than it was but when you start hitting bumps at high speed is where this kit falls short in my opinion. It's like there is not enough damping for the spring rate and therefore the car still kind of bounces around too much just like the old ZSP; not quite as much, but it's still there more than it should be in my opinion.
I don't know, maybe I was expecting a miracle; I did used to drive an E30 M3 and was trying to capture some of that handling feel and I know that's not really possible with a car that weighs about 800 pounds more but I feel like this kit leaves a little to be desired at or above 8/10's. Basically I feel like it's still too bouncy at high speed over bumps and not planted or controlled enough; it's not terrible or anything, just not quite the magic carpet ride that I was hoping for. I probably should have just bucked up for the Ohlins kit which was my second choice and probably will down the line sometime; apparently I can't get the plush feel and total contol I want without going top shelf and spending some $$$. I just hope if I do spend the extra money in the future that my expectations will be met; and that was part of the problem, I couldn't really test out anything before I made the purchase, I was just kind of going on forum advice. Actually on the one hand, with this kit, if you don't push your car hard the kit actually feels pretty good and tight, it just gets a little loose and bouncy for my taste over bumps at say 100 plus mph....
Also, the ride height in the rear is about perfect but the front still needs to settle and come down some. I'll post some before and after pics but right now, the front is still higher than the old ZSP.......i think it will eventually settle though and be just about right......that will hopefully be one plus with this kit; perfect ride height in my opinion.....

[Sticky]

You'd be better off with an aftermarket coil-over setup.

This was for an E9X?

[nikitino25]

You'd be better off with an aftermarket coil-over setup.

This was for an E9X?

Yep probably should have bucked up for the Ohlins kit, my car is an '07 335i coupe....this kit may not be as bad as I'm making it out to be though, I just wanted a bit more of a "tight" feel over high speed bumps....I'm also planning on getting the M3 bits such as front control arms and rear subframe bushings so that should tighten things up a bit as well.

[bigdnno98]

many people go with koni yellows and H&R sport/race, then others go with the KW coilover setups. both are prob leaps and bounds better than the BMW performance springs on OEM shocks

[Nugs]

Yep probably should have bucked up for the Ohlins kit, my car is an '07 335i coupe....this kit may not be as bad as I'm making it out to be though, I just wanted a bit more of a "tight" feel over high speed bumps....I'm also planning on getting the M3 bits such as front control arms and rear subframe bushings so that should tighten things up a bit as well.

Sorry if I encouraged you down the wrong path, there was a bit of confusion on my part as well as I had the performance suspension on a 135i.

[nikitino25]

Sorry if I encouraged you down the wrong path, there was a bit of confusion on my part as well as I had the performance suspension on a 135i.

I think I did see somewhere that the kit is better on the 1 series.......I think I'm good with it for now, I can spend some of the money that I saved on some M3 bits and maybe an LSD

[Nugs]

That sounds like a plan.

[ModBargains.com]

Ohlins will definitely be able to handle high speed bumps due it's Dual Flow Valve Technology. Jeff at Ohlins actually took some time to explain how this valve works and it's pretty cool. Basically under high speed cornering, th eoil cannot flow through the piston under rebound after hitting a bump or uneven pavement on the road. This causes the car to feel unstable and the tire is not able to stay in contact with the surface.

The DFV allows oil to escape quickly providing a stable handling and contact on the road:

NON-DFV COILOVERS:


OHLINS COILOVERS WITH DFV TECHNOLOGY:


This is what separates Ohlins R&T Coilovers from any other systems out there. DFV technology is the byproduct of their long racing heritage and involvement in motorsports.

-Frank

[nikitino25]

UPDATE: Sold the BMW PS kit....thought about swapping the shocks with Bilsteins to see if that cured the "bounciness" that I was experiencing but I don't want to mess around anymore, going with coilovers; probably Ohlins....So, Mr. Modbargains, feel free to shoot me your best price on a set of Ohlins coils......

[Sticky]

UPDATE: Sold the BMW PS kit....thought about swapping the shocks with Bilsteins to see if that cured the "bounciness" that I was experiencing but I don't want to mess around anymore, going with coilovers; probably Ohlins....So, Mr. Modbargains, feel free to shoot me your best price on a set of Ohlins coils......

@ModBargains.com

Feel free to send them a PM as well man.

[nikitino25]

Pm sent...I also forgot to mention that I ended up keeping the front sway bar that came with the BMW PS kit which I felt improved turn in response (maybe it was just the stiffer springs). The bar is the same 26.5mm thickness (I think that's the measurement) as the stock sport ZSP bar but according to BMW sales rep it's stiffer somehow and I would hope so, otherwise why would they add a different bar to the kit....... Anyway, I will post a new seat of the pants review as soon as I install my new coils which will probably be Ohlins. I'm now debating whether or not to go with some stiffer rear springs that come with the Ohlins kit...every other front to rear ratio spring combo for this car seems to be about 1 to 2 front to rear but the Ohlins are nearly 1 to 1. The ohlins rep pretty much said that "that's what our engineers came up with as optimal." Regardless, I will post up a review with whatever combo I go with...

[nikitino25]

One more thing that I thought of recently and just reminded myself of is that if I get the Ohlins kit i will get them with the stock springs first and install this way. If I think the rear springs feels soft then I can additionally get some stiffer rear springs later and install....you don't get a discount (that I know of) for swapping out the springs initially, i.e you pay for the Ohlins springs regardless so why not try them first and then see if you need to upgrade or not.....

[AlexQuattro]

as soon as I install my new coils which will probably be Ohlins.

You can't go wrong with Ohlins that's for sure.

One more thing that I thought of recently and just reminded myself of is that if I get the Ohlins kit i will get them with the stock springs first and install this way. If I think the rear springs feels soft then I can additionally get some stiffer rear springs later and install....

This is a good idea.

[nikitino25]

One more thing that I thought of recently and just reminded myself of is that if I get the Ohlins kit i will get them with the stock springs first and install this way. If I think the rear springs feels soft then I can additionally get some stiffer rear springs later and install....you don't get a discount (that I know of) for swapping out the springs initially, i.e you pay for the Ohlins springs regardless so why not try them first and then see if you need to upgrade or not.....

I guess this is assuming that you are proficient enough to change out the springs yourself if needed, or know somebody that is (in my case). Not sure how hard it would be to change out rear springs on the Ohlins...

[ModBargains.com]

UPDATE: Sold the BMW PS kit....thought about swapping the shocks with Bilsteins to see if that cured the "bounciness" that I was experiencing but I don't want to mess around anymore, going with coilovers; probably Ohlins....So, Mr. Modbargains, feel free to shoot me your best price on a set of Ohlins coils......

PM on the way sir!

-Frank

[Nugs]

One more thing that I thought of recently and just reminded myself of is that if I get the Ohlins kit i will get them with the stock springs first and install this way. If I think the rear springs feels soft then I can additionally get some stiffer rear springs later and install....you don't get a discount (that I know of) for swapping out the springs initially, i.e you pay for the Ohlins springs regardless so why not try them first and then see if you need to upgrade or not.....

That's not necessarily true, you can buy the Ohlins without springs. I know HPA will send them to you with the front struts already assembled with springs (eg swift) and camber plates (eg Vorschlag) if you want.
Here is a table showing what the Ohlins kit comes with compared to what I chose.