Refreshing a BMW E46 M3 for Street Performance with KW V2 Suspension

This allowed us to drop the lower control arm low enough to pry out the spring.

We removed the spring pretty easily at this point.

The stock stuff compared to the KW Variant 2.  Notice the KW shock body is wider for a bigger piston and both the spring and shock are shorter for a lower ride height.

We removed the upper shock mount from the stock shock.

Next, we reinstalled the top mount on the KW shock.  Although dirty the rubber bushing was in good shape so it was reused.

12 comments

  1. is there a reason kw doesn’t provide ride height adjustment that doesn’t effect spring pre-load? Does that artificially limit height adjustment? Does that even matter? Seems like every coilover ever now uses that as a sales gimmick.

    1. Personally, I don’t like preload tuning. It doesn’t affect the spring rate, just the initial force required to move the suspension. It’s better to select the spring rate you need.

    2. coilovers that have separate shock length and spring preload adjustment will have less suspension travel properly designed coilover with only spring preload adjustment for height. some are worse than others, a lot of times application driven.

      1. that is something i had in mind when i asked the question. you could easily slam your car with a divorced adjustment and ruin whatever the shock is trying to do. good point!!

        1. the thing is, its not much better with the divorced adjustment even when its not slammed… a well designed and adjusted setup can do pretty well, but it will never have the same amount of travel as a well designed 1pc setup

  2. Another great article. Thank you!

    For those of us with a vehicle for which KW does not have an application, what other brands of coilovers are quality brands for street-driven cars? I have a 2014 Honda Accord Sport and the only coilover options that I can find for my car are from Tein, BC Racing, and KSport. Knowing that there are far too many variables to consider in this comment section, would you recommend any of these three brands for daily street use? I live north of Atlanta, Georgia, and the roads are overall in good condition (no snow heaves, etc.).

    I had Tein Type Flex on my EG hatch in 2005-2006 and liked them. I have no experience with BC Racing or KSport, but BC Racing offers the option to order any spring rate (with damping to match, apparently). Thanks in advance.

      1. Thanks, Mike. I appreciate the reply.
        No luck with Feal, but Fortune Auto has a 500 Series coilover for my car. Listed spring rates are 10kg/mm front and 6 kg/mm rear. Since the front has strut suspension and the rear is multi-link, those rates seem even more front-biased than the numbers alone would suggest. I don’t know the motion ratio of the rear suspension, but being multi-link, it is obviously less than 1:1. I’m more concerned with a well-damped suspension than with a soft ride, and Fortune Auto seems to offer superior damping. Progress offers an adjustable rear anti-roll bar for my car, so I can use it to supplement rear roll resistance if necessary.
        Since Fortune Auto offers the ability to customize spring rates, are the default rates ideal, or would a stiffer rear be preferable (ie 10/8)? Or, maybe a softer front combined with a stiffer rear (ie 8/8) which would still end up being front biased after the rear motion ratio lowers the rate at the rear wheel. Any guidance would be appreciated. Thank you.

  3. Hi Mike. I want to give you an update: I bought a set of Fortune Auto coilovers and they are fantastic. I had been saving for them, but came across a used low mileage set, with the optional Swift Springs upgrade, on default spring rates (10F/6R). I couldn’t pass up the opportunity, so I bought them and installed them about a week and a half ago. Had I purchased them new, I would have spec’d a stiffer rear spring rate, but that can be rectified in the future whenever the time comes to rebuild/refurbish the dampers. For now, I am very happy with them. The ride is as stiff as should be expected, but the dampers are wonderful, giving a very well controlled ride. Thanks again for the suggestion, Mike! I have been a long-time reader since the Sport Compact Car and Turbo days (subscriber to both to the end), and so took your suggestion to heart. Keep up the good work. Cheers!

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