Suspension and Chassis Questions about your suspension? Need chassis advice?

Rear suspension help ( I have used search)

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Old 05-09-2017, 09:40 PM
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Rear suspension help ( I have used search)

Hello,

I have a question in regards to rear suspension. (i use "search" a lot).

I have an issue with rubbing my rear tires on fender lip.Car has pro-kit springs and KYB struts. I do have Vette rims with currently 295/35/18 on rear (soon to change to a narrower tire). I have a 02 SS Camaro rear end on the car with adjustable panhard bar. Also currently there are NO bump stops on the car.

I had to remove the bump stop area completely. the metal mounting point was rubbing/hitting the inside of my rims. I do not have issues with the axle bottoming out on the floor.

I have had issues with the tires hitting the fender lip. I know part of this is due to tire size (10.5 in rim), just the other day it happened bad enough to damage the side wall to the point where i need to replace the rear tires.

That's the back story.

So my questions are:

First: What size tire should i go with 285/35/18 or maybe 275/35/18?

Second: I want to make sure this does not happen again. I notice lately the rear end looks approx .5 inch lower than the front. I have heard rear that isolators for a fourth gen could boost my ride height. As far as i know the current ones are original.

Are there any other good suggestions out there for this? I have read a lot of different opinions on this.

any help is appreciated.

Cheers,
Old 05-10-2017, 05:53 AM
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Re: Rear suspension help ( I have used search)

What are your rear spring and shocks?

I ran 18x10.5 with the same tires for a long time on the rear, didn't have to anything to the inner wheel well except for a quick hammering at the front lower inside corner, bumpstop intact. Never hit the opening and the car was low.

I say start with stiffer springs and good shocks, konis, nothing less, and considering removing the heavy aftermarket sound system if so equipped.
Old 05-10-2017, 06:10 AM
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Re: Rear suspension help ( I have used search)

Thanks for the reply.

Pro kit springs all around with KYB "silver" struts. Their not that old however I am able to push the rear end down a lot on my own. The front not not so much, very stiff. I do notice the gap between tire and body to be less in the rear.

It terms of fitment I have never had an issue with the inside fender well. Wheels don't hit there. It just the fender lip that has always given me issue.

Back to suspension. I can agree that perhaps the springs need to be either stiffer or taller.

I do have the factory spring that are in good shape. Would putting those back in the rear make a difference perhaps?
Old 05-10-2017, 06:22 AM
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Re: Rear suspension help ( I have used search)

Another simpler option would be to fabricate a new bumpstop

I'm not a fan of the aftermarket.springs that are direct fit. They are never quite right, usually too soft or way to stiff. I've been using weight jacks or coilovers on my firebirds for years now just so I can use spring rates that I need at the ride height I want without a ton of guesswork.

Also are you saying you didn't have to do any hammering for your wheels fitment but you needed to remove the bump atop area?

Your wheels may also be sitting a little to far outboard, but unless you have a spacer, which you don't seem to, there isn't much you can do there.

Last edited by //<86TA>\\; 05-10-2017 at 06:28 AM.
Old 05-10-2017, 05:06 PM
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Re: Rear suspension help ( I have used search)

Thanks for the input.

do you think as a temp solution the factory rear springs that I have or something similar would work?

I plan on doing something with bump stops. Any suggestions on where I should put them?

thank you
Old 05-11-2017, 12:11 PM
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Re: Rear suspension help ( I have used search)

Question.

Since I have pro-kit springs all around. If I change out the rear springs that are soft. Should I be changing the front?

thanks.
Old 05-14-2017, 07:03 AM
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Re: Rear suspension help ( I have used search)

Wow.. I'm having the same issue. Last year I came across a set of c5 zo6 rims/tires, the rears are also 295/35/18 but I have 2in spacers on 85 rear end, there's no rubbing anywhere only on the lip of fender when I hit bumps. I have the competition engineering 1in lowering Springs, adjustable panhard bar.
The only wheel the rubs is the pass side, Driver side no rubbing. I was thinking of trying the coil isolators as I know I don't have them, the stock ones were in rough shape and never replaced them when I put the new coils in. A little confused about what kind to try..
Old 05-14-2017, 07:13 AM
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Re: Rear suspension help ( I have used search)

Here's a few pics.




Old 05-14-2017, 07:24 AM
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Re: Rear suspension help ( I have used search)

Originally Posted by 87_gta
Hello,

I have a question in regards to rear suspension. (i use "search" a lot).

I have an issue with rubbing my rear tires on fender lip.Car has pro-kit springs and KYB struts. I do have Vette rims with currently 295/35/18 on rear (soon to change to a narrower tire). I have a 02 SS Camaro rear end on the car with adjustable panhard bar. Also currently there are NO bump stops on the car.

I had to remove the bump stop area completely. the metal mounting point was rubbing/hitting the inside of my rims. I do not have issues with the axle bottoming out on the floor.

I have had issues with the tires hitting the fender lip. I know part of this is due to tire size (10.5 in rim), just the other day it happened bad enough to damage the side wall to the point where i need to replace the rear tires.

That's the back story.

So my questions are:

First: What size tire should i go with 285/35/18 or maybe 275/35/18?

Second: I want to make sure this does not happen again. I notice lately the rear end looks approx .5 inch lower than the front. I have heard rear that isolators for a fourth gen could boost my ride height. As far as i know the current ones are original.

Are there any other good suggestions out there for this? I have read a lot of different opinions on this.

any help is appreciated.

Cheers,
Well since you need new tires get the 275's and that should do it if you can live with the narrower tire. I have 19 x 10.5 vette wheels. I have my original rear end with wheel spacers. the 275 will look a little stretched on the wheel but(at least on mine) the tire tread ends up just inside the wheel lip.




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