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bulldog19
06-02-2011, 01:59 PM
I have a 68 Camaro with Hotchkis Leaf Spring Rear Suspension. I'm running a 18 x 9 rim w/5-1/2" back spacing and a 275/40 Tire and the tires are rubbing on the outer fender lip when I hit a bump. I have ground down some of the outer fender lip but am cautious of going any further in fear of going through the weld between the outer and inner fender. The tires are rubbing on both sides. If I could raise the car 1/2-3/4" my problem would go away. How can I easily and safely achieve this? The car is a convertible, will not see track time. Maybe a GG autocross if I ever make it to one!
Suggestions and advice is welcomed and appreciated.
Thanks
Bulldog

1red68
06-02-2011, 04:45 PM
The first thought that comes to mind is to install some longer shackles but i don't know how long they would have to be to gain 1/2" at the axle.

MrQuick
06-02-2011, 05:57 PM
1/2" block at the axle mounts.

You can roll the lip up but I suspect it is rubbing where the outer tub turns in a bit. Just above the lip.

MyFriendScott
06-02-2011, 06:00 PM
A 275/40/18 has a diameter of 26.7"
A 275/35/18 has a diameter of 25.6"

Let's say there's a 1" difference there, 1/2" below centerline, 1/2" above centerline. So it seems if you switch to a 35 series sidewall, you'll gain back that 1/2" of extra space.

bulldog19
06-03-2011, 01:56 AM
Thanks for the replys. I was thinking the block was the way to go. I'm afraid to try and roll the lip in fear of craking the paint or what may be under the paint.
I can use the tire change as a last resort.

neki67
06-03-2011, 02:25 AM
Block could have been a nice idea if the axle was beneath the leafs which it isn't. Putting a 1/2 inch block in between the axle and the leaf will only bring the car down 1/2" and your wheel/tire up 1/2" in the wheel well.

Mounting lower sidewall tires will mandate either lower sidewall tires in front to maintain the same stance or shorter front springs. Both options will have the disadvantage of a total lower ride height resulting in scraping headers/exhaust, front spoiler etc. On top of that you will have more space between fender and tire which doesn't look very nice. Going with shorter front springs will give you a "fatter" tire up front than in the rear. Also doesn't look right.

Easiest but not the best suspension wise would be replace the shackles with longer ones.
Some additional supporting airbags (or even airshocks) can also help you. You can maintain (almost) the same stance but since the airbags will have a progressive springrate they will not let you bottom out so easily. Mind you that will also not be the best solution suspension wise but it will not cost you an arm and a leg.

Better solution: how much room is left at the inner wheelwells? You could have a machine shop take away 1/4 - 1/2" of the wheel mounting pad and move the wheel in a bit, giving the clearance you're looking for. Obviously only applicable with alu wheels with thick enough mounting pad.

MrQuick
06-03-2011, 06:22 PM
for some reason I was on a lowering frame of mind. shackles it is.

grenade inspector
06-03-2011, 06:47 PM
shackle it.

Hotchkis
06-06-2011, 04:01 PM
I have a 68 Camaro with Hotchkis Leaf Spring Rear Suspension. I'm running a 18 x 9 rim w/5-1/2" back spacing and a 275/40 Tire and the tires are rubbing on the outer fender lip when I hit a bump. I have ground down some of the outer fender lip but am cautious of going any further in fear of going through the weld between the outer and inner fender. The tires are rubbing on both sides. If I could raise the car 1/2-3/4" my problem would go away. How can I easily and safely achieve this? The car is a convertible, will not see track time. Maybe a GG autocross if I ever make it to one!
Suggestions and advice is welcomed and appreciated.
Thanks
Bulldog

Bulldog - rolling the fender lip is much better than cutting the fender lip because the horizontal lip will cut up a tire. There are two layers of sheetmetal there and it will take some time to massage them. It can be done with minimal amount of paint damage. A body shop will know the best way to do it the cleanest way. Some shops will actually cut the paint with a razor ahead of time. Chipping will depend on how well your wheel lips were prepped.