CorvetteForum - Chevrolet Corvette Forum Discussion - Rear suspension rebuild questions

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Rear suspension rebuild questions

I hope this in the right sub-forum; if not please move...

In getting under my new-to-me C4 the past couple nights, I've discovered that the ~5 year old VBP rear strut rods that the previous owner installed have disintegrating bushings which appear to cause excessive negative camber. This is exaggerated when backing up, causing the wheels to be visually ~15 degrees inboard at the top from the bottom. It's so bad that the outer two tread blocks on the tire don't touch the ground. When I pull it forward and/or drive it, the camber relaxes significantly but is still visibly too negative for street driving.

Before I go chasing ghosts, I'm seeking advice on what steps to take here with the strut rods. The car was set up for occasional autocross/track days, so I understand a little negative camber...but I want to bring it back to stock or close to it. I have the OE strut rods and would like to use them, but they have some poly bushings pressed into them and the OE eccentric bolt is very loose by at least 1/16" and unusable currently. Should I find some OE sized bushings for the OE rods and reinstall to factory or get some decent adjustable strut rods and leave it adjustable? The trailing arms and sway bar have matching VBP poly bushings which seem fine, it's just the VBP strut rod bushings that are chunking out.

The OE rear spring (base model) seems fine visually but I wonder if this needs addressing too? The car only has 35k miles, but it was mildly tracked a few times a year for the last 16 years.

I'll add pics when I get a chance.

I don't know the VBP parts, can you get new bushings for them? If so that might be the easiest solution here. Unsure but it looks like there are some washers missing from the current setup.

If you want to go back to oem, there are replacement poly bushings available for them. For the slop issue, sounds like either the bushings are worn or the metal sleeve is missing from them.

Honestly, I think VB&P is more or less out of business for now. They haven't been responsive on getting parts to anyone lately. I'd get all poly bushings out of the rear suspension - it creates bind and resultant non-linear handling. The best option is rod-ended links, such as those sold by Banski. I'd replace your camber rods with those.

that car was a driver and apparently it was driven. On other cars I purchased heim ends separately and installed them in panhard rods; individual heim joints are available from any of a number of sources and should install into your existing VBP camber rods.

Quote:

Originally Posted by mtwoolford (Post 1597399181)

I didn't think of that, but it's a good thought. You'd have to match the threads in your VBP camber rods, but that's probably doable. You'd need to stack washers or cut some spacers from the appropriate sized steel tubing to make the rod ends snug inside the tabs and lugs where the bolts go through - the rod ends aren't nearly as wide as the bushing shells you have in there now. That's not a big deal, though.

Take a look here:

https://www.currieenterprises.com/co...SAAEgJievD_BwE

you would have to see if the sizes and thread pitches would be compatible with those VBP bars.

VBP might have bought their ends from those folks or someone with a similar product.

Do the VBP ends have grease fittings ?

Here are some other rod end bushings, once again sizes would have to be matched up.

https://www.polyperformance.com/susp...orged-housings

Finding these rod ends leads me to believe VBP didn't actually manufacture their ends. The chore will be spending some quality Google to find the correct rod ends that they used. The OP will (or others) will need to determine sizes and thread pitch of the existing ends. Remember that one set comprises of one end being right hand pitch and the other a left hand pitch.

VBP's website is "down for maintenance".

look for "rubber bushed rod ends" lots pop up such as these

https://www.speedwaymotors.com/shop/...d_style:233810

Those look like Johnny joints and are rebuildable.
https://www.currieenterprises.com/CE-9112NRK

years ago when i had access to a machine shop i reverse engineered a set of camber rods and trailing arms and machined them. the rod ends were 5/8-18 unf right and left threads and had a 5/8 dia hole in the balls. then i machined spacers. since then i purchased the camber rods and trailing arms from banski, nice pieces.

Quote:

Originally Posted by Sleazy Rider (Post 1597405778)

since then i purchased the camber rods and trailing arms from banski, nice pieces.

Good Choice. They really improve drivability

Thanks for the input, guys. Sorry it took so long to sit down and get back in the forum.

No, the ends do not have grease fittings and it does appear to me that some washers are missing as well. I think I'm going to just get a full, matched set of new bars with the Heim joints and call it a day...even as much as I enjoy a deep dive on Google.

I cranked in the bars to minimum adjustment and all of the excessive negative camber is gone when reversing and now the wheels sit vertically as they should. I'm sure camber is still off but for now it's driveable short distances until the new equipment is installed and the car is re-aligned.