Suspension help, unsprung weight
Thread Starter
Pro
Joined: Mar 2002
Posts: 630
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Suspension help, unsprung weight
Like many of you C4 owners I have modded the car with different wheels, tires, brakes and rotors and I think I may have caused myself some problems. I have a 93 coupe with just under 22k on the clock, about 2yrs ago I switched out the factory wheels and tires with AFS 5 spokes 9.5" all the way around and Goodyear GSD3 275/40-17 tires. At that time I really didn't notice anything different except slightly more wheel rebound and I figured it was being caused by the 5/6 extra lbs. of wheel and tire weight on the front end, no big deal. Last summer I put on the C5 brakes, again added I'm guessing 4/5lbs. more to each side on the front and noticed considerable more wheel/ tire rebound. This winter instead of putting on a set of Powerslots that I had purchased which weigh the same as a regular C5 rotor I picked up some Baer 1pc rotors and put those on. The Baer rotors easily weigh 5/6lbs more than stock C5 rotors. I feel that I have added 15/16lbs. of unsprung weight maybe more to each side on the front end and the car drives just awful. I know the car only 22k miles but it is 12yrs old, there is no apparent sign of shock leakage, but could the shocks be weak? Are there HD shocks out there that will help, or am I not looking at this problem correctly? Any suggestions?
Le Mans Master
Joined: Apr 2000
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From: Amateur driver on open course.
Re: Suspension help, unsprung weight (9T3JIM)
Could be time for new bushings. My rear spring bushings were shot. I replaced them recently when I did new shocks. There could be more severe issues, but my suggestion would be to look at all the front and rear bushings and replace if needed. Good Luck! :thumbs:
Team Owner
Joined: Sep 2001
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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Re: Suspension help, unsprung weight (9T3JIM)
It can be shocks going downhill, but they should not have failed with only 22K, age is a factor but mileage for Bilsteins is the more important one.
It could be alignment time, bushing replacement, shocks, its hard to tell from your description if its an actual problem or something youll just have to live with.
It could be alignment time, bushing replacement, shocks, its hard to tell from your description if its an actual problem or something youll just have to live with.
Large Impressive Member
Joined: Jul 2003
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Re: Suspension help, unsprung weight (BAM92)
If you've added as much unsprung weight as you say then I think the shocks could very well have gone south by now. I'd have them checked first.
Thread Starter
Pro
Joined: Mar 2002
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Re: Suspension help, unsprung weight (Corvette Kid NC)
Thanks to all who responded, turns out it was an alignment problem. 2/3yrs ago I had the alignment set to VBP daily street specs or so I thought. Took the car in for an alignment this morning and took the VBP catalog with me to show the techs, turns out the actual settings were closer to the advanced street settings beacause of this I was just getting tossed around with every bump in the road. I had the tech do an alignment back to factory specs and everything is perfect, Its fun to drive the car again.
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