Ride height problems

[L88 crazy]

Hey!

This is a problem I'm sure all 68 to 82 Corvette owners have dealt with. A sagging rear end. I have had this problem a while. I took it to a local corvette restoration shop and they said "You've got a bad rear spring. It's got to be replaced.". Thats what they did. It stayed level for a day and it was sagging again. I went back to the shop they had no ideas as to what was wrong. I recently went to Corvettes at Carlisle and saw that every 68 to 82 Corvette have 50 series tires on the back, I have 30 series on the rear of mine. There was also a rear spring company there. That man said that my spring mounting posts are too short and are pulling the spring flat. Is he right or could it be that I need to have taller tires? Or is it something else? How can I fix this? Many thanks to all who have advice. THANK YOU!!!

 

[82ColEd]

Hey L88 Crazy, welcome to the CAC !
Here is my 2 cents: Whenever my car is in the shop, it stays a little higher because the shocks get pulled out and stay out a tad more. Once the car is back on the ground they come back down. My pipes are about 2.5 inches off the ground, so whenever i go through a low pull (over a hill, then back down into a ditch the other side), they scrape.. Looks great though at nite, sparks flying 'n all..
I'll check the tires, but i got the standard Goodyears on it.
Dont forget to

 

[Bob Chadwick]

I'm assuming that you are talking about the spring end bolts here. Do a search here as the issue has been addressed on numerous occasions but my recollection is that the longer the bolt the lower the rear and vice versa. It seems backwards but I understand that thats the way it works. So if it is too low tighten the nut.

 

[82ColEd]

I checked on the tires: BF Goodrich Radial T/A 255/60 R15's
Hope this helps..

 

[JohnZ]

Neither the length of the spring link bolts nor tire size have any effect whatsoever on spring deflection - the only thing that affects spring deflection is the weight of the car. Overall tire diameter will affect chassis-to-ground clearance, but won't have any effect on the spring - it's still carrying the same load it was when the car had stock wheels and tires.

 

[vmrod]

I would tighten the spring bolts too. It's an easy way to adjust the ride height.

 

[brusso]

L88 Was the spring guy talking about the four bolts that go through the "dogbone" on the diff cover? Those are the only bolts that I could think of that may flatten the spring.

When I installed my 7 leaf hd spring, it didn't have the 8th leaf. Well it was more like a spacer than a leaf. It was only long as the diff was wide. Without it, tightening the 4 bolts to the diff flattened the curved sping to the flat diff mounting surface. This changed the hight by almost a half inch.

 

[john1977]

Im with L88, I to would like to raise the sagging rear of my C3

 

[Bob Chadwick]

It's the bolts on the ends of the spring, not the center, that adjust the ride height.