Peavey

I've been trying to track down what is causing my 67 to handle so poorly, it just doesn't want to track down the road decent and I think it is getting worse. I've owned this one since 2020, and right away it didn't seem to handle right. A more recent, noticeable development is that I am getting some darting when I accelerate hard and then lift off the throttle - it will pull to the left when I let off the gas.

I don't have a lift at home, so I have taken it to a few local mechanics that are generally pretty good but they claim everything looks right.
At this point, I have:

1.) Installed new ball joints and tie rods
2.) Installed a new, complete power steering kit from ZIP.
3.) Tightened the steering box lash - there is no play from the steering wheel to the PS control valve.
4.) Had the rear differential rebuilt with new bearings (I was doing the seals anyway).
5.) Complete alignment.

I know that a C2 will not handle like a modern sports car, but my baseline is my 65 C2, which handles just fine and is a pleasure to drive. I know that the factory PS units aren't great, but my 65 also has a factory style PS unit. The only thing that is not apples to apples between the 2 cars is that the 65 has radial tires and the 67 has bias plies, but the difference in handling is huge, to the point where it is borderline unsafe to drive and certainly no fun to drive.

My instinct is that there is something loose in the rear, given the behavior when I lift throttle, but no one has been able to find anything. Does the handling behavior point to one specific component of the rear end? Anybody know of someone in Minnesota that really knows these cars and might be able to help me troubleshoot? I am at about my wit's end with this.

ChrisBlair

How old are the tires? Sounds dumb but...you sure they are round? Tire shaving used to be a thing. And actually in 2014 I had to have a Pirelli shaved a hair.

elongated stud hole in a wheel?

Half shaft walking?

dcamick

You did not mention your trailing arm condition.......Does the rear end "sway"? It that what you are feeling?

jim lockwood

^^^^THIS^^^^

Deteriorated trailing arm bushings and/or deteriorated camber rod bushings will cause squirrelly behavior.

JohnnyRay

Generally, when a car exhibits issues like this it is due to a change in toe-in caused by worn/dry suspension bushings. In a C2 Corvette, it could also be rear bearings. Also, you don't mention the age or condition of the tires. If they are more than 7 years old, they could contribute to squirrely handling.

I have not lived in the TC area for a long time now, so don't know if the same players are still active in Corvette specific service. I don't believe Corvette Specialties is still around. Could try Dan's Complete Automotive in Blaine...but any frame and alignment shop should be able to readily check the suspension for loose parts. If you do find an issue in the rear, could be time for a complete trailing arm replacement that would cover multiple issues. We used Van Steel on my 65...

mrg

You mentioned an alignment was done. The handling issue sounds like the trailing arm shims may have come out if they weren’t secured in place, allowing the trailing arm to slide across the front mount bolt from side to side.




John

Yellow6t7

Did you tighten the front stabilizer bar links?

427Hotrod

Worn inner axle yokes will do it also. Sure sounds like something is moving around in the rear.

JIM

leif.anderson93

Combine post #4 and #6 and I'd bet you'll find your problem.

Peavey

Tires are definitely old. I was hoping to wait to replace them until after I got the suspension issues worked out to avoid getting some funny wear on new tires. From what I can tell from the DOT code C2F6409 I think they were made in the 40th week of 1989 or 1999.

Peavey

I may have to circle around to re-examining the trailing arms. I asked to have them checked when the rear end was getting rebuilt and he said the trailing arms and rear bushings looked fine, but....

I think I may end up just replacing the trailing arms and rubber parts just to eliminate them as a possible source. I do think it is something in the rear suspension.

leif.anderson93

And, they may have been fine. If they're Poly bushings, they can look great one day and disintegrate the next. If it turns out the bushings are bad, replace with stock rubber bushings.

Peavey

I wish Timm Brothers was still around - the farm that they operated out of was only about 20 miles from where I live. My brother used them for his 66 and I had talked to them about a 67 roadster before that whole operation dissolved. They had many C2's there in various states and they were going to assemble one for me, with fresh paint for $25,000.00. They never finished it. Yes, that was many years ago.

Is Van Steel a parts supplier or a shop? I am inclined to just go that route and replace everything with fresh parts. The bearings in the differential were replaced, but if you mean the individual wheel bearings I haven't checked those. I think I will double check those tomorrow when I get a little time.

Peavey

I have to check my invoice from ZIP when I ordered parts for the rear end, but I think I replace the axle yokes at that time.

Peavey

Thank you everyone for the suggestions. I haven't tried doing much of the work myself for this because of a lack of time, and but also I just can't physically tolerate it like I used to when I was younger. But it looks like I am going to go back to my favorite mechanic and ask him to put it up on a lift and walk through things with me. This gives me a good checklist to go through. Now if the snow would just hold off for a few more weeks.....

Nowhere Man

they are a parts supplier. but there is no need to start making whole sale changes to the car, if this was all of a sudden problem then doing a methodical diagnostic of the suspension is needed. all the points to look for where noted above. but knowing the type of bushings that was used and their condition is key here

JohnnyRay

Van Steel is both a new parts supplier as well as a rebuilder. We bought new trailing arms complete with bearings and brakes, new front springs and Bilstein shocks from them. Also had them rebuild the posi diff for us...

https://www.vansteel.com/

JF in MI

I would be pretty surprised to find an alignment shop that knows how to set rear toe on a C2-C3. Those that have someone that does know probably wouldn't admit to it. Usually they'll set the camber and "say" it's done which usually makes the toe-out worse along with the handling. Just my opinion.

64L76

Do you have radials on your 67? If yes, did you have it aligned to accommodate the radial tires? Alignment specs C2s with radials is different than OEM alignment specs for bias ply. Remember - radials were not available on any C2s from the factory. If your car is set up for bias ply tires and you have radials you will be all over the road at speeds above 30 - 35. At 60 is its like you don't have control of where the front tires are pointed. Sounds like what you are experiencing.

JohnnyRay

Perhaps you can share the "radial" specs and/or explain the differences so we all come away from this conversation more knowledgeable on the topic?