23. Öhlins Road & Track – coilover
This is part of my extended review thread that you can find in its entirety here: 335i E90 LCI - Experiences and review of various modifications (long!) but that I reposted here in order to make this part easier to find.
As already indicated in this review
, I was not satisfied with my Bilstein B16 Ride Control suspension due to several reasons. During daily driving I was particularly annoyed at the ride height that was far too low even on the highest setting (front spoiler scraping on the floor each time I went into an underground parking lot), the clunking of the front dampers in spite of having replaced them a few thousand kilometers ago and last not least at the vertical movements of the rear axle at high speeds.
I decided therefor that I needed a different suspension. But which one? I informed myself assiduously on various forums as well as with a number of friends. I excluded another Bilstein suspension due to the above mentioned hassles. In principle I wanted to have a coilover again so that I could set the ride height exactly as I wanted it, and the next suspension would have to redress all shortcomings of the B16 RC and improve on the ride comfort. Bordering on squaring the circle? In the end there were several alternatives that I was considering:
- AC Schnitzer sports suspension:
Manfred Wollgarten of AC Schnitzer has an excellent reputation for his know-how in suspension matters, and I had a very positive feedback about this sports suspension from an acquaintance. In addition, AC Schnitzer offers several versions of this suspension, depending on the engine (and therefor weight) which in my book means they really know what they're doing. That suspension has the parts no. 313090310 and costs 1153,- EUR.
- KW Variante 3:
In the past few years, KW has gained an excellent reputation due to the fact that they have a suspension dyno available which has considerably improved their products. I had also heard several very good feedbacks on the KW V3; the advantage as compared to the AC Schnitzer suspension was in particular the adjustability (ride height, compression and rebound of the dampers). Price: ca. 1700 EUR.
- Öhlins Road & Track:
A very good friend of mine had already changed with his 335i from the Bilstein B16 RC to the Öhlins Road & Track
and had tested it extensively on the Nordschleife. In addition, a motorsports garage near the Nürburgring has been an official Öhlins dealer for years and warmly recommended me this coilover. Price: ca. 2100 EUR.
In the end I decided for the Öhlins coilover. Öhlins has - coming from bikes - an excellent reputation as high end solution for suspensions, in particular in the racing sector. In addition, I could resort to the experience of a garage I knew quite well (and which had already installed this suspension in an Alpina B3 S Biturbo E90 just a few weeks earlier), as well as the feedback of a very experienced friend of mine. As far as the price range was concerned, the Öhlins was approximately as expensive as my Bilstein coilover and was therefor in an acceptable price range.
Öhlins disposes of a patented technology that is called DFV (Dual Flow Valve) which ensures that the same characteristics are there on rebound as on compression, due to the damper fluid having a consistent path of flow in both directions. This means that the wheel and tyre can quickly and effectively resume their important position back on the ground, providing grip and traction. The quicker opining of the DFV on road imperfections is supposed to add to the ride comfort. Over uneven surfaces, the compliancy of the Öhlins allows the car to crest bumps and pot-holes, whilst still keeping it stable and in control. Here's a diagram illustrating the functioning of the DFV technology:
In addition, Öhlins has developed a system that deals with the heat that dampers generate due to the friction of the piston moving within the damper. Öhlins has developed a unique needle bleed valve which expands with temperature, closing the gap that the fluid travels through, maintaining a consistent damping rate and avoiding a change of handling characteristics while driving.
In addition to the ride height which is adjusted by leaving the spring seat in its perfect position whilst the lower flange spins on the threaded body (and therefor does not compress or extend the spring), compression and rebound can also be adjusted (not separately though), and the Öhlins McPherson struts also feature camber adjustable upper and lower mounts. Lastly there's the possibility to use different springs with higher spring rates and valve the dampers for this accordingly. Out of the box, the Öhlins leads to a lowering of about 15mm, and the spring rates are 60Nm (front) and 70Nm (rear).
Here's a picture of the front damper:
The installation and adjusting of the suspension was done by BMSracing e.K. in Leimbach at the Nürburgring. The owner Uli Baumert has been an Öhlins specialist and dealer for years and obviously had no problem installing and adjusting the coilover.
After a few test drives, a moderate lowering of the ride height and the standard rebound/compression settings (7 clicks) seemed to be ideal for both daily driving and a few quick laps on the Nordschleife.
Some photos of the installation:
At the same time, adjustable toe links from Rogue Engineering were installed, which should prevent lateral movements in the rear during acceleration - and adjustable toe is a particular advantage in the case of height adjustable coilovers (as these may lead to a positive toe that cannot be corrected with the OEM toe links). I ordered these through Harold at HP Autowerks
; the price is currently 289 USD for the black anodized version in aluminium. That's what they look like:
And here's how they look once installed:
When picking up my car I was obviously very curieus, as the suspension is one of the most important components of the car - on the Nordschleife as well as while driving it in normal traffic.
My requirement had been very clear before installing the suspension - having a higher ride height than with the Bilstein suspension. To my pleasant surprise this was possible without any problems, so that I can now drive into underground parking lots and go over speed bumps without fearing of scraping my front spoiler. It does not look overly low slung either anymore, and even while driving on the 'Ring in sections such as the "Karussell" where the suspension goes into a lot of compression there is still some margin:
Also during a normal bend on the 'Ring:
I'm also very pleased with the handling of the Öhlins suspension. Similar to the Bilstein suspension, there's almost no vertical movement, and quick left-right combinations do not disturb the car at all - together with all the M3 components that have been installed so far, it really handles extremely sharply and the car snappily follows any steering input. At high speeds the car feels very safe and composed; also challenging passages on the 'Ring such as the last part of the Fuchsröhre where you approach an uphill left bend at more than 200 km/h and the suspension goes into an extreme compression (attention: typically evokes panic attacks from unwary passengers) do not make the suspension nervous at all. Also, high speed passages with bumps - such as the "Pflanzgarten" section on the Nürburgring or driving at 250 km/h on an uneven Autobahn in Germany - which with the Bilstein suspension previously unsettled the car and led to disquieting vertical movements at the rear axle did not faze the car at all now and the rear axle maintained an excellent contact to the road.
Due to the various M3 suspension components that are installed in my car, the suspension is far stiffer than in an ordinary 335i anyway. In combination with the previous Bilstein suspension I found it sometimes a little too much on the harsh side, in particular on some of the bad roads we have here in Europe. The Öhlins by contrast is quite a bit more supple and absorbs uneven roads much better. Obviously you can't expect any Rolls Royce like ride with a coilover, but it is quite surprising how much residual comfort remains. At least for me the Öhlins suspension is suitable for long distance trips - and for use on very even circuits such as the Hockenheimring or the Grand Prix circuit at the Nürburgring it is still possible to adjust the dampers to a stiffer setting. The spring rate also seems to me very well adapted to the car, and at least for now I do not see the necessity of changing the spring rates (e.g. with Swift springs such as some have done).
• Problems / disadvantages?
I have now been driving the Öhlins suspension for over 10 months, have done more than 15.000km with it and quite a few laps on the Nürburgring. Until now there's no clunking or any other noise coming from the suspension, and no problems have arisen during the installation or use so far. The substantial price may of course be considered a drawback, but for me the Öhlins is worth it and offers an excellent value for money.
For those living in Germany: A TÜV certificate comes with the Öhlins suspension, so that it can easily be officially registered in the car papers.
In summary: Recommended without reservation!