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      05-02-2016, 02:59 PM   #1
M3 Number 86
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Anyone replace rear springs on KW Clubsport?

Going to up my rates in the rear and need to know sizing.

I believe the stock is 220mm which is around 8.7".

Going for an 800lb spring in the rear and realize it won't compress as much. So trying to figure out the correct length to get.

I've been told to use a 6.5" spring with helper or an 8" without helper.

Sound right?
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      05-03-2016, 12:37 AM   #2
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Can the club sport dampers handle that much spring? What's the limit?
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      05-03-2016, 09:43 AM   #3
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Quote:
Originally Posted by elim11
Can the club sport dampers handle that much spring? What's the limit?
It can. Shit I just found that I don't have my helper springs in in the rear do may have to buy some or get a same length spring lol
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      05-03-2016, 01:19 PM   #4
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You will need a 9" spring in that rate. Hyperco makes them.
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      05-03-2016, 01:20 PM   #5
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Quote:
Originally Posted by RickyBobby
You will need a 9" spring in that rate. Hyperco makes them.
Did that affect your ride height adjustability?
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      05-05-2016, 12:30 PM   #6
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Quote:
Originally Posted by M3 Number 86 View Post
Going to up my rates in the rear and need to know sizing.

I believe the stock is 220mm which is around 8.7".

Going for an 800lb spring in the rear and realize it won't compress as much. So trying to figure out the correct length to get.

I've been told to use a 6.5" spring with helper or an 8" without helper.

Sound right?

On my track car, I'm running 150Nmm/140mm in the front with no helpers (see my strap solution in another thread, works great) and 180Nmm-200mm in the rear with helper, all springs from KW. The shocks can very well handle this and more.
All this depends on your driving, weight and ride height. My car is with driver & 3/4 gas at 3610lbs, ride height in the rear is at 566mm (fender to 18" rim).
Hope that helps
.
.
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      05-05-2016, 01:31 PM   #7
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Quote:
Originally Posted by jakob66
Quote:
Originally Posted by M3 Number 86 View Post
Going to up my rates in the rear and need to know sizing.

I believe the stock is 220mm which is around 8.7".

Going for an 800lb spring in the rear and realize it won't compress as much. So trying to figure out the correct length to get.

I've been told to use a 6.5" spring with helper or an 8" without helper.

Sound right?

On my track car, I'm running 150Nmm/140mm in the front with no helpers (see my strap solution in another thread, works great) and 180Nmm-200mm in the rear with helper, all springs from KW. The shocks can very well handle this and more.
All this depends on your driving, weight and ride height. My car is with driver & 3/4 gas at 3610lbs, ride height in the rear is at 566mm (fender to 18" rim).
Hope that helps
.
.
Thanks! I asked you about the strap as the fronts already have no helper. My rears are stock with no helper so gonna go do some math to see if an 8" at a higher rate will be ok at my correct height. I feel like someone stole my ear helper springs at some point lol
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      05-05-2016, 03:09 PM   #8
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Quote:
Originally Posted by M3 Number 86
Quote:
Originally Posted by RickyBobby
You will need a 9" spring in that rate. Hyperco makes them.
Did that affect your ride height adjustability?
Not at all. My standard spring perches allow my mildly lowered ride height. I tried 8" springs and the car was too low at the top of my adjustor.
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      05-05-2016, 09:00 PM   #9
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Quote:
Originally Posted by RickyBobby View Post
Not at all. My standard spring perches allow my mildly lowered ride height. I tried 8" springs and the car was too low at the top of my adjustor.
do you mean at the lowest perch setting? that would have raised it though right? or am i wrong?
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      05-06-2016, 02:07 PM   #10
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Why not swap in KW Competition springs on your Clubsports? I know Malek at MRF Engineering is running that exact setup.
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      05-06-2016, 02:09 PM   #11
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Quote:
Originally Posted by Hujan View Post
Why not swap in KW Competition springs on your Clubsports? I know Malek at MRF Engineering is running that exact setup.
because I want to determine my own spring rates. no offense, don't follow that guy and never will.
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      05-09-2016, 08:29 AM   #12
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Quote:
Originally Posted by M3 Number 86 View Post
Thanks! I asked you about the strap as the fronts already have no helper. My rears are stock with no helper so gonna go do some math to see if an 8" at a higher rate will be ok at my correct height. I feel like someone stole my ear helper springs at some point lol
Sorry I missed your request about the strap. Here's a picture with the car on jacks. That's the only position the straps see loads. I have them since last year on all TT events and they work flawless. They give me enough space for 295/30 Hoosiers.

Name:  20160227_154901.jpg
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      05-09-2016, 09:46 AM   #13
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Quote:
Originally Posted by jakob66
Quote:
Originally Posted by M3 Number 86 View Post
Thanks! I asked you about the strap as the fronts already have no helper. My rears are stock with no helper so gonna go do some math to see if an 8" at a higher rate will be ok at my correct height. I feel like someone stole my ear helper springs at some point lol
Sorry I missed your request about the strap. Here's a picture with the car on jacks. That's the only position the straps see loads. I have them since last year on all TT events and they work flawless. They give me enough space for 295/30 Hoosiers.

Attachment 1419509
Thanks I meant that I've already seen them!

So I checked under the car over the weekend and findings were strange. Mine came with a 140-200 spring which is already what I was looking for

While doing my research I found that the rears were 120-220 springs. These are for the newer sets sold. So I answered my own question as to why spec sheets posted all said 800 in the rears. These are the old specs.

So older sets came with a 9kg/14kg setup and the newer ones come with a 11kg/12kg setup. Its weird that they upped the fronts and lowered the rears.
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      05-09-2016, 09:41 PM   #14
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Quote:
Originally Posted by M3 Number 86 View Post
Thanks I meant that I've already seen them!

So I checked under the car over the weekend and findings were strange. Mine came with a 140-200 spring which is already what I was looking for

While doing my research I found that the rears were 120-220 springs. These are for the newer sets sold. So I answered my own question as to why spec sheets posted all said 800 in the rears. These are the old specs.

So older sets came with a 9kg/14kg setup and the newer ones come with a 11kg/12kg setup. Its weird that they upped the fronts and lowered the rears.
Yeah, its all about KW's marketing. The KW CS are made for guys that do some track events, but they still have to do dd comfortably. My setup is way too harsh for dd, little torturous.
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      05-09-2016, 10:38 PM   #15
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Quote:
Originally Posted by jakob66
Quote:
Originally Posted by M3 Number 86 View Post
Thanks I meant that I've already seen them!

So I checked under the car over the weekend and findings were strange. Mine came with a 140-200 spring which is already what I was looking for

While doing my research I found that the rears were 120-220 springs. These are for the newer sets sold. So I answered my own question as to why spec sheets posted all said 800 in the rears. These are the old specs.

So older sets came with a 9kg/14kg setup and the newer ones come with a 11kg/12kg setup. Its weird that they upped the fronts and lowered the rears.
Yeah, its all about KW's marketing. The KW CS are made for guys that do some track events, but they still have to do dd comfortably. My setup is way too harsh for dd, little torturous.
Yeah lol

Right now its good 625/800 I'll up later to about 750/850 if needed.

Feel bad for those thinking they are getting 800 lbs in the rear and getting 675 lol
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      05-09-2016, 11:22 PM   #16
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Quote:
Originally Posted by M3 Number 86 View Post
no offense, don't follow that guy and never will.
well now i'm curious...

Quote:
Originally Posted by jakob66 View Post
Sorry I missed your request about the strap. Here's a picture with the car on jacks. That's the only position the straps see loads. I have them since last year on all TT events and they work flawless. They give me enough space for 295/30 Hoosiers.

Attachment 1419509
the straps don't see loads when you lift a wheel on an off camber corner? have what length is the strap? you could get something like a beard limiting strap, but it would just be for bling i guess.


also, what wheel specs are you running? any rubbing with that setup?
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      05-10-2016, 12:44 AM   #17
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Quote:
Originally Posted by roastbeef
Quote:
Originally Posted by M3 Number 86 View Post
no offense, don't follow that guy and never will.
well now i'm curious...

Quote:
Originally Posted by jakob66 View Post
Sorry I missed your request about the strap. Here's a picture with the car on jacks. That's the only position the straps see loads. I have them since last year on all TT events and they work flawless. They give me enough space for 295/30 Hoosiers.

Attachment 1419509
the straps don't see loads when you lift a wheel on an off camber corner? have what length is the strap? you could get something like a beard limiting strap, but it would just be for bling i guess.


also, what wheel specs are you running? any rubbing with that setup?
Its max length is when the showing would get unseated from the top mount.
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      05-10-2016, 12:53 AM   #18
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the limiting straps are made in incremental lengths from 8 to xx inches...
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      05-10-2016, 09:25 AM   #19
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Quote:
Originally Posted by roastbeef View Post
well now i'm curious...



the straps don't see loads when you lift a wheel on an off camber corner? have what length is the strap? you could get something like a beard limiting strap, but it would just be for bling i guess.
also, what wheel specs are you running? any rubbing with that setup?
Roastbeef
The front sway bar will push the other wheel. Unless you go airborne with both front wheels at the same time the straps won't see load. And if I go airborne (hopefully not any time soon!) it doesn't matter, they are strong enough.
Straps, I couldn't find any in my specific length and width (and they are pricy) and 2nd I didn't want to use a heavy adjusting bolt as you do have to adjust to your specific ride height. This setup was very cost effective .

I run 295/30/18 Hoosiers (on Arc8 10.5" ET27) up front with only 3mm spacers, so not much wheel offset at all which steers very nice.

.
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      05-10-2016, 11:05 AM   #20
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Quote:
Originally Posted by jakob66 View Post
Sorry I missed your request about the strap. Here's a picture with the car on jacks. That's the only position the straps see loads. I have them since last year on all TT events and they work flawless. They give me enough space for 295/30 Hoosiers.

Attachment 1419509
Wow. Great idea

Please post as much as you can about this setup. It seems like an easy way to not user helper springs and have plenty of space!
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      05-10-2016, 01:36 PM   #21
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Quote:
Originally Posted by M3 Number 86
Quote:
Originally Posted by jakob66
Quote:
Originally Posted by M3 Number 86 View Post
Thanks! I asked you about the strap as the fronts already have no helper. My rears are stock with no helper so gonna go do some math to see if an 8" at a higher rate will be ok at my correct height. I feel like someone stole my ear helper springs at some point lol
Sorry I missed your request about the strap. Here's a picture with the car on jacks. That's the only position the straps see loads. I have them since last year on all TT events and they work flawless. They give me enough space for 295/30 Hoosiers.

Attachment 1419509
Thanks I meant that I've already seen them!

So I checked under the car over the weekend and findings were strange. Mine came with a 140-200 spring which is already what I was looking for

While doing my research I found that the rears were 120-220 springs. These are for the newer sets sold. So I answered my own question as to why spec sheets posted all said 800 in the rears. These are the old specs.

So older sets came with a 9kg/14kg setup and the newer ones come with a 11kg/12kg setup. Its weird that they upped the fronts and lowered the rears.
So why did you want to change the rear springs in the first place? Did the car not handle to your liking with your current springs?
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      05-10-2016, 04:24 PM   #22
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Quote:
Originally Posted by RickyBobby
Quote:
Originally Posted by M3 Number 86
Quote:
Originally Posted by jakob66
Quote:
Originally Posted by M3 Number 86 View Post
Thanks! I asked you about the strap as the fronts already have no helper. My rears are stock with no helper so gonna go do some math to see if an 8" at a higher rate will be ok at my correct height. I feel like someone stole my ear helper springs at some point lol
Sorry I missed your request about the strap. Here's a picture with the car on jacks. That's the only position the straps see loads. I have them since last year on all TT events and they work flawless. They give me enough space for 295/30 Hoosiers.

Attachment 1419509
Thanks I meant that I've already seen them!

So I checked under the car over the weekend and findings were strange. Mine came with a 140-200 spring which is already what I was looking for

While doing my research I found that the rears were 120-220 springs. These are for the newer sets sold. So I answered my own question as to why spec sheets posted all said 800 in the rears. These are the old specs.

So older sets came with a 9kg/14kg setup and the newer ones come with a 11kg/12kg setup. Its weird that they upped the fronts and lowered the rears.
So why did you want to change the rear springs in the first place? Did the car not handle to your liking with your current springs?
It felt soft in the rear relative to the front. Part of it was probably my mind knowing I upped the fronts fing with me. And it was on slow corners on the street. I'm gonna play with my adjustments at the next event and see how it feels.
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