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      11-11-2012, 05:50 PM   #1
Porschefile
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Removing KW CS helper springs to allow wider front tires

I have read about this a few times and have come to the conclusion that I probably need to do this, but there is no discussion on exactly what must be done and no pics.

If I just remove the helper spring (even if it is fully compressed at full droop, which I believe it is) I imagine I would have to adjust the spring perch upward significantly to keep the same ride height?

The problem is that I have 0 toe already, so if I screw up ride height at all then I will need an alignment to fix the toe.

Anyone actually done this?
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      11-11-2012, 07:22 PM   #2
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You will definitely change ride height as you'll be removing a stacked up part of the suspension. Make measurements before and after from hub or bottom wheel lip to fender. Watch lowering both front wheels at the same time to make sure the coils seat without the helper springs.

Post some pics since here aren't any!
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      11-11-2012, 07:37 PM   #3
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Thanks, I will take pics if/when I do it.
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      11-11-2012, 08:09 PM   #4
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Quote:
Originally Posted by Porschefile View Post
I have read about this a few times and have come to the conclusion that I probably need to do this, but there is no discussion on exactly what must be done and no pics.

If I just remove the helper spring (even if it is fully compressed at full droop, which I believe it is) I imagine I would have to adjust the spring perch upward significantly to keep the same ride height?

The problem is that I have 0 toe already, so if I screw up ride height at all then I will need an alignment to fix the toe.

Anyone actually done this?
You'll have to raise the spring perch 29mm (about 1-1/8") to get the same ride height. Make sure that there's enough thread above the perch before you start.

Basically, you're shortening the spring stack by removing 25mm of helper spring that's pressed from a spiral into a cylinder by the weight of the car, and 4mm of spring spacer.
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      11-11-2012, 08:50 PM   #5
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^great info!
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      11-12-2012, 03:27 AM   #6
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Quote:
Originally Posted by Car54 View Post
You will definitely change ride height as you'll be removing a stacked up part of the suspension. Make measurements before and after from hub or bottom wheel lip to fender. Watch lowering both front wheels at the same time to make sure the coils seat without the helper springs.

Post some pics since here aren't any!
Another tip is to place a piece of painter's tape on the fender, so that you know where you took your 'before' measurement!

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Originally Posted by JAJ View Post
You'll have to raise the spring perch 29mm (about 1-1/8") to get the same ride height. Make sure that there's enough thread above the perch before you start.

Basically, you're shortening the spring stack by removing 25mm of helper spring that's pressed from a spiral into a cylinder by the weight of the car, and 4mm of spring spacer.
Matches my data sheets exactly
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      11-12-2012, 08:52 AM   #7
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Quote:
Originally Posted by JAJ View Post
You'll have to raise the spring perch 29mm (about 1-1/8") to get the same ride height. Make sure that there's enough thread above the perch before you start.

Basically, you're shortening the spring stack by removing 25mm of helper spring that's pressed from a spiral into a cylinder by the weight of the car, and 4mm of spring spacer.
Awesome, thanks!
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      11-12-2012, 11:29 PM   #8
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huh we were just discussing this last week...who will be the first to actually try it? 295's upfront?
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      11-13-2012, 08:17 AM   #9
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huh we were just discussing this last week...who will be the first to actually try it? 295's upfront?
275 conti slicks on 18x10 up front for now. But I'd like to run bigger since my street setup is 295 rear on a 19x11 and I have to reduce grip on the rear for track to 275 to maintain the proper F/R handling balance.
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      11-13-2012, 01:17 PM   #10
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If you look at the early APEX wheel GB threads (started by APEX), I think they said you can stuff an 18x10 with a 285/30R18 wheel on the front with a small spacer on stock suspension. Just looking at it, don't see how you can get a 295 on the front.
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      11-13-2012, 03:08 PM   #11
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Quote:
Originally Posted by bigjae1976 View Post
If you look at the early APEX wheel GB threads (started by APEX), I think they said you can stuff an 18x10 with a 285/30R18 wheel on the front with a small spacer on stock suspension. Just looking at it, don't see how you can get a 295 on the front.
Right, but the KW CS spring perch interferes with a 275/35/18 in front unless it is very high ride height (according to Apex, on 18x10). I went ahead and ordered some 5mm spacers just in case, but I plan on just taking out the helper. I'd really like to run at least 285/285 at some point, but I guess I'll have to take measurements and see. I know Richbot and others have ran larger than that for AX, but on a narrower rim IIRC.

Frankly I think 275 up front should provide pretty good front grip, but the rear feels so good with 295's to put down power that it irritates me to have to either have a bit of natural understeer (stagger) or run narrower in rear to balance it out.
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      11-14-2012, 03:17 PM   #12
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KW Tech Support strongly rec'd against this. I just talked to them today, and they said that if the spring wasn't seated then it could come loose when jumping curbs or in other situations and cause disastrous results. Thoughts?
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      11-14-2012, 04:02 PM   #13
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It really depends on your ride height.

If your helpers are more or less fully compressed at full droop, it is perfectly fine to remove them as long as you have enough thread on the strut to move the height adjuster upwards.

If your helpers are not fully compressed at full droop, you should not remove the helpers.

But, since you ordered spacers already, why not try the spacers first?

PS: Can you take a picture of your front suspension? Make sure both of your front wheels are off the ground, or disconnect the sway bar.
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      11-14-2012, 04:10 PM   #14
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Quote:
Originally Posted by Richard@M-World View Post
It really depends on your ride height.

If your helpers are more or less fully compressed at full droop, it is perfectly fine to remove them as long as you have enough thread on the strut to move the height adjuster upwards.

If your helpers are not fully compressed at full droop, you should not remove the helpers.

But, since you ordered spacers already, why not try the spacers first?

PS: Can you take a picture of your front suspension? Make sure both of your front wheels are off the ground, or disconnect the sway bar.
Front is roughly 13" center of roundel to the fender, on 265/30/19. I guess I will just run the spacers, I'd just hate to get all the way down to Savannah and then have to dismantle the suspension.

Sure, I'll get one Thursday. I'm installing Bimmerworld studs and stuff anyway so it'll be in the air.
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      11-14-2012, 06:05 PM   #15
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The sway bar should keep your single wheel droop from unseating the spring during curbs and such. Can the helper be installed at the top?
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      11-14-2012, 06:46 PM   #16
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which KW are you running?
for example - the stock front KW Clubsport spring is a 90-170. 90newton - 170 long.
You can order a 90-140 from KW. I know some guys running it because of the same reason.
And by the way: KW recommends to upgrade to a 120newton front spring as the 90 is basically too soft and your car is rollin too much.
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      11-15-2012, 08:08 AM   #17
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Quote:
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The sway bar should keep your single wheel droop from unseating the spring during curbs and such. Can the helper be installed at the top?
I'm not 100% sure, but I don't see why not.
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      11-15-2012, 08:09 AM   #18
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Quote:
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which KW are you running?
for example - the stock front KW Clubsport spring is a 90-170. 90newton - 170 long.
You can order a 90-140 from KW. I know some guys running it because of the same reason.
And by the way: KW recommends to upgrade to a 120newton front spring as the 90 is basically too soft and your car is rollin too much.
Interesting. The front is already too stiff relative to the rear though (the pound rate went up way more in front than rear, compared to stock). I guess if I ran the 140mm spring with the helper that would also eliminate the issue. I run clubsports.
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      11-15-2012, 09:38 AM   #19
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This could be contributing to your understeer...too stiff in the front.
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      11-15-2012, 09:43 AM   #20
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Quote:
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This could be contributing to your understeer...too stiff in the front.
I agree completely. I just don't get why everyone else with the same coils and springs doesn't seem to experience it.
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      11-15-2012, 12:17 PM   #21
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Where are your damper settings at? Just curious.

You use the conti scrubs (275 square), right? i ran those for awhile and I would experience under steer. IMHO, those scrubs are crap unless you know what car they're from, how many heat cycles, and which corner they are off of. I've since had Dunlop z1* and RS3s with the same mods (dinan st2 & GC plates)...haven't had any understeer except in an auto-x scenario with a 10mph turn around.

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...too stiff in the front.
That's what she said.
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Last edited by bigjae1976; 11-15-2012 at 12:22 PM.
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      11-15-2012, 03:30 PM   #22
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Quote:
Originally Posted by bigjae1976 View Post
Where are your damper settings at? Just curious.

You use the conti scrubs (275 square), right? i ran those for awhile and I would experience under steer. IMHO, those scrubs are crap unless you know what car they're from, how many heat cycles, and which corner they are off of. I've since had Dunlop z1* and RS3s with the same mods (dinan st2 & GC plates)...haven't had any understeer except in an auto-x scenario with a 10mph turn around.



That's what she said.
I have tried a few settings and have ended up back at recommended settings for the dampers. I actually haven't tried the conti's yet, my issue is with the staggered AD08s.
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