Lowering rear suspension ?

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Jul 26, 2009 | 10:08 PM

Double G

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From: Clinton Twp. Michigan

Lowering rear suspension ?

I want to lower the rear of my 01 C5 Coupe 1 inch on the stock bolts. How many turns or bolt height change do I need to back off? My guess is 1/2 the remaining threads?

Jul 26, 2009 | 10:11 PM

Umrswimr

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From: Overwhelmed as one would be, placed in my position.... DFW, TX

St. Jude Donor '05

However far you unscrew it, that's how far the car will be lowered. IIRC, you can reach it with the car on the ground...

Jul 26, 2009 | 10:24 PM

Double G

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From: Clinton Twp. Michigan

Does that mean that 1 inch on the bolt gives you 1 inch at the quarter panel wheel lip?

Jul 26, 2009 | 10:49 PM

Y2Kvert4me

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From: Gone

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St. Jude Donor '03

Quote:

Originally Posted by Double G

Does that mean that 1 inch on the bolt gives you 1 inch at the quarter panel wheel lip?

Not really.

The control arm is at an angle, and since the adjustment point is inboard of the wheel, it takes less adjustment than that to realize the drop at the wheel. It's closer to a 2/3 ratio.

To get a full inch drop at the rear, with no other mods (like cutting bushings or using longer bolts), back the nuts off until you see only a thread or two above the nut. This is about the most you can get out of the stock bolts. If you want more drop, swapping to longer bolts (6.5-7" long) will give you the ability to lower more.

The rear is very easy to adjust and fine-tune....you can do it w/o even jacking the car up. Just slide under the rear and adjust as needed. Loosen the nuts to lower, tighten them to raise it.

Jul 26, 2009 | 10:53 PM

Double G

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From: Clinton Twp. Michigan

I'll buy that.

Jul 27, 2009 | 02:20 AM

Last C5

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From: Vancouver Washington

The bolt itself is 12 or 13 turns per inch and apply the 2 to 3 ratio to that. So about 8 turns should get you somewhere near and inch at the fenderwell.