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      08-24-2020, 11:06 AM   #3
Kankles
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Quote:
Originally Posted by swagon View Post
Quote:
Originally Posted by Kankles View Post
Need some forum "math in public" assistance.

With more track days planned in the future I'm looking to upgrade (at least the front progressive springs) to a linear spring for more aggressive set-up. I'm also running millway street CPs FWIW.

From what I've read the V3 struts are same as the club-sport but with different valving. So I need to be careful not to go too stiff and exceed the strut capabilities.

As I'm in EU "KW Racing" springs are likely the best option as they have 61mm ID linear springs, etc. If I were in the US I'd probably do a swift upgrade from Harold at HP as they've been doing these upgrades at least since E46 days.

My biggest question that I hope to get answered here is what spring length would you guys recommend in order to keep same height adjustment? Also, taking into consideration the helper spring and "helper spring separator" into the overall spring length.

Front progressive spring is 220mm uncompressed, 175 while compressed (max ride height).

This makes me think I need at least a 170mm front spring combined with 60mm helper (18mm stack height) and needle bearing plate (5mm), but I'm not 100% sure.


The club sport uses an 80-220 front spring, so even stiffer. I'm also open to spring rates but I'm considering 60 Nmm for the front (342 lbs/in).

Any insight greatly appreciated
I don't know where in the EU you are located, but I'd give one of the shops around the Nordschleife a call. Schirmer, Raeder or Laptime Performance all do custom suspension work, for example. Or even KW themselves since they also are able to make custom builds.
Ok, thanks for the tip, appreciate it! I'm in Holland.

Email is currently out with KW. I'll keep going down the list if they can't help. I imagine they can as I shouldn't be the first to switch the V3 to linear springs.

After doing a bit more research I've found the clubsport uses front 170 length with 80 Nmm springs. So that will get me a bit closer to where I want to be considering helper spring, spring divider, top roller bearing, etc
Appreciate 0