KW V3 Coilovers Progressive Spring to Linear

[Good]

To those that run KW Variant 3 coilovers, and have converted to linear springs, What spring rates did you use? And what is your vehicles weight?

[Sergmann]

I ran V2's for two track seasons on swift 500 lb springs in the front and 840 in the rear. the car was very well settled but did understeer a bit at the limit. Contrary to what most will say about the shocks not being able to handle the spring rates I was totally happy with the setup. I have since sold them and they went right back in a track car.

[Acetech]

V2s here street setup 400lb front 600lb rear, very happy with it.

[Jersey_M3]

What modifications are needed to make this work. And which springs sizes are they

[Acetech]

I run 6” Swift springs in front with tuner street camber plates and 60mm spring adapter that can be ordered with the plates.
In the rear I use TC Kline bee hive springs, 6.5”
I use weight jacker spring perches but you don’t have to.

[r4dr]

I run 6” Swift springs in front with tuner street camber plates and 60mm spring adapter that can be ordered with the plates.
In the rear I use TC Kline bee hive springs, 6.5”
I use weight jacker spring perches but you don’t have to.

Did you have to do anything with the lower perch? I thought I remember them having to be machined down slightly to fit 60mm springs.

[Tbonem3]

Did you have to do anything with the lower perch? I thought I remember them having to be machined down slightly to fit 60mm springs.

I just assumed the bottom perches on KW were 60mm. Any more info on that?

What modifications are needed to make this work. And which springs sizes are they

Like above, I assume it's just a matter of getting 4 60mm dia linear springs with some 60mm upper perches to work with whatever plates you have, then some 60mm locating cones for the rear or use your existing adjusters with the stock rubber pad.

[r4dr]

I just assumed the bottom perches on KW were 60mm. Any more info on that?

HPA down in SoCal has made a "kit" to convert KW V1/2 to linear springs for a while. I inherited KW V2s with my car so I was looking into this a while back. Based on their forum posts about their kit, the KW lower seats are 61mm in diameter so they need to be machined down 1 mm in diameter to fit 60mm springs. See their post here:

https://www.e46fanatics.com/threads/how-to-finally-get-performance-out-of-your-kw-coilovers.778203/page-3#post-12439721

Their kit is a bit pricey for what it is IMO. If you get the front seats machined (pretty cheap for any machine shop to do) and pair them with camber plates, you can do it yourself easily.

More info on their product page: https://hpashop.com/KW-Swift-Spring-...on-e36-e46.htm

[r4dr]

My main hangup on doing this is whether the cost of a) converting to Swift linear springs and b) probably rebuilding the shocks as they've done 30k+ miles already, are worth it versus going with R&T and doing it once and doing it right.

I've never been able to figure out the quality of KW's dampers in general and their longevity. Based on their target market, I don't hear many detailed reviews about it. This thread is some of the first track-based feedback on them I've heard.

[Tbonem3]

Hmm, I suppose you could then just use 2.5" springs which are 63.5mm. 1.25mm of overhang is nothing.

[Acetech]

My original KW front lower spring perches fit the 60mm Swift springs fine without modifications

[T.J.]

Could also use 65 mm spring with these

https://www.ycwsuspension.com/shop/swift-springs/coilover-springs/spring-adaptor/

or you know KW sells a wide variety of linear rate 62mm springs

[Sergmann]

My main hangup on doing this is whether the cost of a) converting to Swift linear springs and b) probably rebuilding the shocks as they've done 30k+ miles already, are worth it versus going with R&T and doing it once and doing it right.

I've never been able to figure out the quality of KW's dampers in general and their longevity. Based on their target market, I don't hear many detailed reviews about it. This thread is some of the first track-based feedback on them I've heard.

I went through this exact process and ultimately deiced to upgrade my setup. If I had it to do all over again I would have simply upgraded from the jump. I sold my kit for less than the sum of the parts and I had a bunch of my time in the setup.

As for the lower front spring seats they measure just over 61mm. I machine mine down to 60mm, they are plastic, which is a simple job if you have access to a lathe. Once you do this there is no going back to the original springs unless you buy new lower spring mounts.

[r4dr]

Bumping this thread…

Does anyone know the thread diameter and pitch of the adjustment collars & spring seats on the KW strut body?

[maupineda]

M52x1.5