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      11-15-2012, 10:25 PM   #23
bigjae1976
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OK...FYI...I might end up trying 275/35R18s fr and 285/35R18s rr.
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      11-16-2012, 02:03 AM   #24
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Quote:
Originally Posted by Car54 View Post
Can the helper be installed at the top?
The issue is not where the helper is (it actually comes at the top from KW), the issue is the total length of the spring + helper which could interfere with the wheel/tire.

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Originally Posted by Porschefile View Post
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.
Don't forget leverage. The spring in the rear is seated inboard, so the effective spring rate at the wheel is much less than the indicated spring rate.

The conventional knowledge is to soften the front if you have understeer. Unfortunately as you can see from the flow chart, the actual process is a lot more complex.

Also, when you increase the rate in the front, you will need to match the rear spring with it. Try the 520F/800R rate first with a squared set up. You should like the balance much more.
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      11-16-2012, 08:35 AM   #25
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Quote:
Originally Posted by Richard@M-World View Post
The issue is not where the helper is (it actually comes at the top from KW), the issue is the total length of the spring + helper which could interfere with the wheel/tire.



Don't forget leverage. The spring in the rear is seated inboard, so the effective spring rate at the wheel is much less than the indicated spring rate.

The conventional knowledge is to soften the front if you have understeer. Unfortunately as you can see from the flow chart, the actual process is a lot more complex.

Also, when you increase the rate in the front, you will need to match the rear spring with it. Try the 520F/800R rate first with a squared set up. You should like the balance much more.
Exactly, but that just makes it ever more likely that the front is too stiff. The rear effective rate is in the 200's IIRC; the front is in the 400's. I pulled the wheels last night to install studs, and the helpers are not fully compressed at my current ride height so I left it alone. I test fit the 275/18x10 combo and it rubbed without and spacer and did not rub with a 5mm spacer. I took a couple of pics of the strut if anyone still wants to see.
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      11-16-2012, 02:42 PM   #26
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Quote:
Originally Posted by Porschefile View Post
Exactly, but that just makes it ever more likely that the front is too stiff. The rear effective rate is in the 200's IIRC; the front is in the 400's. I pulled the wheels last night to install studs, and the helpers are not fully compressed at my current ride height so I left it alone. I test fit the 275/18x10 combo and it rubbed without and spacer and did not rub with a 5mm spacer. I took a couple of pics of the strut if anyone still wants to see.
Glad to hear that everything worked out!
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