1966 C2 Rear Spring Height - Am I too High?

[Edmund C.]

Guys: My Mechanic (Nathan) just called after installing my new rear spring (bought from Volunteer Corvette and painted the proper color). He indicated that it's a bit higher in the rear now and has a 1/2" lilt to the left driver's side. Nathan is a good hand (and a great well trained Mechanic), yet, is not sure what the issue is (if anything). Any thoughts or guidance would be appreciated. Many thanks as always. Best, Ned

[Patrick H.]

Re: 1966 C2 Rear Spring Height - Am I too High?

Look at the "related threads" down at the bottom of this page. It is a common issue with reproduction springs that the car will sit too high.
As a result, I always recommend reconditioning good originals over using a new one. In fact, I bought a good used one a couple of years ago just in case I ever need it in the future (and the price was right, too).

You might be able to have it re-arched a bit lower by a local spring shop.

[Bob R.]

Re: 1966 C2 Rear Spring Height - Am I too High?

If you installed new bushings they will compress after you drive a bit and the car will drop about an 1" or so.

[Larry M.]

Re: 1966 C2 Rear Spring Height - Am I too High?

Ed:

Some replacement springs will sit high..........especially until you get some wear miles on the new spring and rubber suspension bushings.

HOWEVER, when did your mechanic tighten all the rear suspension and spring bolts?? They must not be tightened until the car is back on the ground on all four wheels AND the inside of the car is loaded with any additional weight to bring the rear suspension height to the dimension shown in the Factory AIM. It is in the AIM and concerns the factory height design dimension. In my 1967 AIM it was on page 157 Titled: Rear Trim Heights.

If the bolts are tightened early, or at the wrong installed height, the suspension is set at this incorrect point and wants to try and remain there. Often times, this results in a rear height that is too high. Tightening the spring bolts before weight is on the tires can also crack the rear axle cover.

Larry

[Francis F.]

Re: 1966 C2 Rear Spring Height - Am I too High?

Sounds like good advice,I will have to check mine as it looks a touch on the high side,with a orig.G m replacement purchased inlate1970s
Francis

[Richard M.]

Re: 1966 C2 Rear Spring Height - Am I too High?

Ned, Strange that one side it tilted 1/2" more(DS) than the other(PS). Did he check the leaf spring center bolt? Repros bolt heads are too tall and don't fit into the differential carrier and the top leaf won't lay flat on the carrier mount boss. Last 3 times I did springs I had to grind the center bolt head. Maybe the spring is tilted due to the center bolt. See this Post for details.

Also, are you using original outer spring bolts? I just went through this on a 66 using a Eaton reproduction 9-leaf. Rear sat apx 1 1/4" high. I used longer outer spring bolts(more threads) to get the ride height to spec by drawing the nuts up higher, hoping eventually it may relax over time and the originals can go back on.

Patrick is right though, using originals is best or get the repro re-arched. But if you want functionality for now, longer bolts would help solve the "raked look" if that's a issue.

Rich
PS - I'll be in Frisco for the Regional so we'll have to meet.

[Donald H.]

Re: 1966 C2 Rear Spring Height - Am I too High?

I had a similar issue with my 67 when I bought it. It had a replacement rear spring, one from China. It sat to high. Whoever installed the spring set didn't realize that were shipping retainers holding the spring in place and did not remove these. I removed them, but the car still sat to high.

Probably a long shot, but just make sure that the spring set you have does not these shipping retainer still on the springs

I replaced with a set of Eaton reproductions which I have been happy with.

One other thing you could check is flip the springs side to side and see if the lilt changes sides.

Don

[Edmund C.]

Re: 1966 C2 Rear Spring Height - Am I too High?

Gents: I picked up the Vette tonight. It still looks about 1 inch too high. How badly will I get hammered by the NCRS Judges for this? She rides nice and the properly painted Spring and Delco Shocks look super; however, it's high and reminds me a bit of a jacked up Charger I had back in High School in 1978. It's a bit of a bummer and Julie's going to murder me if I spend any more cash this month on cars. Question: Can I put some spacers in the front to level her out a bit? Any cheap guidance would be appreciated as the Lone Star Regional is coming up. Many thanks. Best, Ned

[Donald H.]

Re: 1966 C2 Rear Spring Height - Am I too High?

I'm not a judge, but I would think that a judge would take no more than 1 point and maybe only mark with a dot for ride height if they even notice it.

I suspect that the springs will continue to settle some as you drive the car.

I would be more concerned as to whether the springs closely resemble originals. The 9-leaf spring on Volunteer Vette's web site looks to have straight ends.

Don

[Bob R.]

Re: 1966 C2 Rear Spring Height - Am I too High?

If they replaced the bushings the car will drop a little within a week or so as the new rubbers break in maybe even an inch.

[Richard M.]

Re: 1966 C2 Rear Spring Height - Am I too High?

Ned, To help get it relaxed and compressed while it's sitting in the garage, maybe put several heavy bags of sand spread out in the rear storage area. Just lay a tarp or blanket in there to minimize clean up when removed. Before you put them in roll the car tires over pieces of cardboard sandwiched with plastic bags so the tires camber out. Or simply roll the car 10 feet both directions before parking it with the weight in there.

Rich

[Bob W.]

Re: 1966 C2 Rear Spring Height - Am I too High?

I have a question for Richard Mozzetta and Larry Mulder. In this thread and another one you say to not tightening the bolts for the spring at the rear cover as it can crack it. So how tight should they be? Finger tight-snug I'am not sure.

Thanks Bob.

[Bob R.]

Re: 1966 C2 Rear Spring Height - Am I too High?

Use a wrench and get them snug but not fully tight, once the weight of the car is on the spring you can crawl under and finish tightening the bolts

[Larry M.]

Re: 1966 C2 Rear Spring Height - Am I too High?

Use a wrench and get them snug but not fully tight, once the weight of the car is on the spring you can crawl under and finish tightening the bolts

I agree...........probably just compress the lock washers to flat. Lowering the car unto its wheels (suspension) pushes the spring tighter to the rear axle housing spring support pad and not looser........so this is not a concern. You want the spring to be able to adjust slightly as needed as weight is applied to the suspension.

When the car is back on its wheels AND the ride height is established per the AIM (you may have to add some weight inside the car.....I did), then get under the car and tighten the various suspension bolts to spec.

Make absolutely certain the the two spring bolts that thread into the blind holes in the rear axle cover plate are not too long and contact the metal casting in the cover plate. Just this weekend I helped a friend remove the rear axle assembly from his 1969 Corvette because the previous owner used too long of bolts and cracked the rear cover. He saw it dripping fluid when he was under the car a few weeks ago. The previous owner had used some sealant to seal the threads and cover/stop the leak, but eventually the sealant began to deteriorate and leak fluid due to time.

I try and leave about 2 threads of extra space between the end of the bolt and the cover plate metal casting when the bolt is fully tightened. This is around 3/16 inch clearance. Make certain you do the same............accurately measure these two bolts and your clearances, and cut them to fit if needed (I needed to cut both of mine).

Just the changes in the current thickness of the reproduction spring liners from OEM thickness can create the issue with the spring bolts into the blind holes. Don't take a chance.

Larry

[Bob W.]

Re: 1966 C2 Rear Spring Height - Am I too High?

Thank you Bob and Larry for your quick reply. Now time to move on.

Bob