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      08-30-2012, 04:44 AM   #1
leigh
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Compression and Rebound settings for KW Clubsports

could someone give me a little help on what the best compression and rebound settings are for kw clubsports on the track. i know its not the same for all tracks but where would be best to start?
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      08-30-2012, 09:55 AM   #2
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Go with recomended KW settings to start with, adjust from there. Do search in this section for clubsport and you'll find lots of advice on top of this
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      08-30-2012, 11:47 AM   #3
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KW stock setup is:

Front:
Rebound-6
Compression-6

Rear:
Rebound-9
Compression-6

All numbers are clicks out from full stiff. I ran this setup at Barber and it feels very good, planted all over the track. There was some slight understeer, especially in low speed sections, which I plan on adjusting the front some to cure. Rear is perfect IMO on street tires.
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      08-31-2012, 01:10 AM   #4
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Not sure if it carries over but I have a s2000 with v3s and most track guys hate the recommended settings. I think they are meant to induce understeer and give a more compliant ride for street driving. The best thing for you to do is maybe start 2 full settings closer to stiff and then follow normal adjustments based on tires and amount of oversteer/understeer
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      08-31-2012, 01:57 AM   #5
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Quote:
Originally Posted by zslow6 View Post
Not sure if it carries over but I have a s2000 with v3s and most track guys hate the recommended settings. I think they are meant to induce understeer and give a more compliant ride for street driving. The best thing for you to do is maybe start 2 full settings closer to stiff and then follow normal adjustments based on tires and amount of oversteer/understeer
2 settings closer to stiff on both front and rear will not affect understeer/oversteer significantly. It is the bias that matters. I think dropping compression on the front slightly, or increasing rebound, is the way to go from stock (rec'd). Several other members have been quite pleased with CS on track in E92 M3's. Not at all discounting your experience in S2k's, just saying that for our cars the stock settings are at least close.
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      11-13-2012, 04:22 PM   #6
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Bump for an update. I have played with the settings a bit.

I ran rec'd settings, R: 6/9 C: 6/6, and found it had a little understeer on corner entry and mid corner. This is with -2.5 camber and 0 toe.

I softened front rebound to 9, to make it R: 9/9 C: 6/6, and it noticeably worsened the understeer. It made the car push bad with my setup and driving style (295/265 AD08).

Returning to the rec'd settings cured the understeer (mostly). I then stiffened front rebound 2 clicks to see if that would completely eliminate understeer, and did not notice a substantial difference between rec'd settings and R: 4/9 C: 6/6. I am now back to the rec'd settings.

It is my thinking that the stagger I have is causing my understeer issues, which should be cured by my new 18x10 275/275 conti slick setup. I will report back after testing. I will say that even though the car understeers some, it drives amazingly on track and is much more planted than stock. My 2c.

Edit: I would like to get input from other KW CS drivers, perhaps there is something I'm missing that is causing mild/moderate entry/mid corner understeer. I read JAJ's post(s) many times and I know he was pleased with R: 11/11. I don't know if the difference is stock PS2 vs. wider AD08, or driving style, or some other factor. More knowledgable folks please chime in.

Last edited by Porschefile; 11-13-2012 at 04:30 PM.
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      11-13-2012, 08:44 PM   #7
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Quote:
Originally Posted by Porschefile View Post
Bump for an update. I have played with the settings a bit.

I ran rec'd settings, R: 6/9 C: 6/6, and found it had a little understeer on corner entry and mid corner. This is with -2.5 camber and 0 toe.

I softened front rebound to 9, to make it R: 9/9 C: 6/6, and it noticeably worsened the understeer. It made the car push bad with my setup and driving style (295/265 AD08).

Returning to the rec'd settings cured the understeer (mostly). I then stiffened front rebound 2 clicks to see if that would completely eliminate understeer, and did not notice a substantial difference between rec'd settings and R: 4/9 C: 6/6. I am now back to the rec'd settings.

It is my thinking that the stagger I have is causing my understeer issues, which should be cured by my new 18x10 275/275 conti slick setup. I will report back after testing. I will say that even though the car understeers some, it drives amazingly on track and is much more planted than stock. My 2c.

Edit: I would like to get input from other KW CS drivers, perhaps there is something I'm missing that is causing mild/moderate entry/mid corner understeer. I read JAJ's post(s) many times and I know he was pleased with R: 11/11. I don't know if the difference is stock PS2 vs. wider AD08, or driving style, or some other factor. More knowledgable folks please chime in.
Is your understeer during initial turn-in, transitions or over bumps, etc (i.e., transients/transitions/when the damper is working) OR steady-state understeer? It sounds like your issue might be steady-state understeer which would be addressed with different spring rates, alignment settings (e.g., more F toe out), sway bar settings or ride height changes (e.g., try raising the rear height, leaving the front alone).
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      11-14-2012, 03:16 PM   #8
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Quote:
Originally Posted by M3SQRD View Post
Is your understeer during initial turn-in, transitions or over bumps, etc (i.e., transients/transitions/when the damper is working) OR steady-state understeer? It sounds like your issue might be steady-state understeer which would be addressed with different spring rates, alignment settings (e.g., more F toe out), sway bar settings or ride height changes (e.g., try raising the rear height, leaving the front alone).
initial and mid corner. I guess it is steady state. Maybe the rake is not enough? I have around .6" higher front than rear, similar to stock. And toe is zero.
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      11-14-2012, 03:26 PM   #9
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Quote:
Originally Posted by Porschefile View Post
initial and mid corner. I guess it is steady state. Maybe the rake is not enough? I have around .6" higher front than rear, similar to stock. And toe is zero.
I'd try changing the rake so the rear is 0.25-0.5" higher than the front (start at 0.25" and then increase to 0.5"). Dropping the rear ride height relative to the front (or increasing front relative to rear) will increase steady-state understeer (other variables come into play but this is generally the case). Depending on your current ride heights, if possible, I'd start by lowering the front first before raising the rear (i.e., always initially start working on the end with the issue because it will help to increase overall grip).
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      11-14-2012, 03:28 PM   #10
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Quote:
Originally Posted by M3SQRD View Post
I'd try changing the rake so the rear is 0.25-0.5" higher than the front (start at 0.25" and then increase to 0.5"). Dropping the rear ride height relative to the front (or increasing front relative to rear) will increase steady-state understeer. Depending on your current ride heights, if possible, I'd start by lowering the front first before raising the rear (i.e., always initially start working on the end with the issue because it will help to increase overall grip).
Thanks for the info. The problem is I just got the damn thing aligned and I know dropping it .25" will toe out a good bit. Is there any way dropping it that amount would still be an acceptable amount of toe?
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      11-14-2012, 03:34 PM   #11
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Quote:
Originally Posted by Porschefile View Post
Thanks for the info. The problem is I just got the damn thing aligned and I know dropping it .25" will toe out a good bit. Is there any way dropping it that amount would still be an acceptable amount of toe?
Not ideal for ultimate grip/handling (it's always a compromise!) but you could split the difference - drop the F 0.125", raise the R 0.125" to minimize F-R toe changes. This still won't give you the correct rake (rear higher than front) but it's a change that should still help to reduce overall understeer - if it helps then decide if you want to realign your car and set the rake...
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      11-14-2012, 03:39 PM   #12
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Thanks, I'll try that.
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      11-14-2012, 04:15 PM   #13
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Quote:
Originally Posted by Porschefile View Post
Bump for an update. I have played with the settings a bit.

I ran rec'd settings, R: 6/9 C: 6/6, and found it had a little understeer on corner entry and mid corner. This is with -2.5 camber and 0 toe.

I softened front rebound to 9, to make it R: 9/9 C: 6/6, and it noticeably worsened the understeer. It made the car push bad with my setup and driving style (295/265 AD08).

Returning to the rec'd settings cured the understeer (mostly). I then stiffened front rebound 2 clicks to see if that would completely eliminate understeer, and did not notice a substantial difference between rec'd settings and R: 4/9 C: 6/6. I am now back to the rec'd settings.

It is my thinking that the stagger I have is causing my understeer issues, which should be cured by my new 18x10 275/275 conti slick setup. I will report back after testing. I will say that even though the car understeers some, it drives amazingly on track and is much more planted than stock. My 2c.

Edit: I would like to get input from other KW CS drivers, perhaps there is something I'm missing that is causing mild/moderate entry/mid corner understeer. I read JAJ's post(s) many times and I know he was pleased with R: 11/11. I don't know if the difference is stock PS2 vs. wider AD08, or driving style, or some other factor. More knowledgable folks please chime in.
Perhaps this chart will help: http://www.m3post.com/forums/showthread.php?t=735413

The most effective way of solving mid-corner understeer is going to a staggered set up, which you are already doing.

I would not directly apply one car's 'optimal' setting to another car because there are too many variables. The driver, tires, wheels, suspension set up, race track... all completely different.
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      11-14-2012, 04:25 PM   #14
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Quote:
Originally Posted by Richard@M-World View Post
Perhaps this chart will help: http://www.m3post.com/forums/showthread.php?t=735413

The most effective way of solving mid-corner understeer is going to a staggered set up, which you are already doing.

I would not directly apply one car's 'optimal' setting to another car because there are too many variables. The driver, tires, wheels, suspension set up, race track... all completely different.
Thanks! I'll try to lower the front and see how the square setup does too.
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