bbeck

I'm looking at going with a poly kit and am wondering if anyone has positive or negative input on suppliers and kits they offer. Looking to place an order for this in the next few days.

Also, what are you running for the crossmember bushings above the diff?

Tampa Jerry

I installed poly in my trailing arms in my 66. After three years they turned to glass and broke apart. I do have side pipes and this makes a difference. Exhaust gas collected in the pocket where the trailing arms connect to the frame. I have a few friends where the exact same thing happened. I pulled the arms off and switched back to rubber. As far as the differential mount is concerned, the poly is not the same size as the rubber mount. My drive shaft hit the tunnel with the poly mount. I switched out to rubber and the problem disappeared. I have a spare poly differential mount for sale. Jerry

hugie82

I purchased energy suspension for the front and rear. I didn't start the rear rebuild but the front is showing some signs of the bushng being crushed. I'm hard on my car but not abusive and I was was starting to second guess doing the rear. The only bright spot in bad poly bushings is it's very easy to replace when the time comes. No air chisels and 20 ton presses to get them out.

bbeck

So, is anyone happy with their poly bushings? This is what I normally run in other vehicles and don't have problems- besides maybe a little squeaking

bbeck

any good feedback?

SteveTheCorvette

I, unfortunately, do not have enough miles on my poly bushings to provide longevity feedback, but I will say I have seen much more information against poly than for poly.

That being said, I like the handling feel of new poly vs old rubber.
Also, I bought the energy suspension poly rebuild kit for the rear and was not proud of that purchase. I replaced most components back there and most components come with bushings. I only used a couple from the kit (trailing arm pivot) and they were press in rather than staked. The "press in" caps came out when I was installing the trailing arm in the car. Not sure if this was a one-time thing or not.

The poly bushings make the ride more firm/harsh, if you want a comfortable cruiser, go with rubber. If you want a sportier ride, use poly. If you want to make sure the bushings last another 30 year, well, you know rubber is up to that task.

bbeck

My number 1 concern is eliminating the wheel hop
I don't mind a sporty ride over comfort- I'm not too familiar with corvette ride quality as my brother's is the only other one I've ridden in or driven.

MajD

When I rebuilt my rear end, I used rubber in the trailing arms because of the rotational motion around the bolt. I originally had rubber bushings in the strut rods but they kept disintegrating. Since their motion is rotational as well, I went with a heim joint setup instead of trying poly strut rod bushings. I used rubber cross member insulators because they are integrated into the bushing sleeve and help hold the cross member level. For $35, you can buy an aftermarket kit that consists of some round plates that bolt over the cross member bushings and reduce the cross member rotational motion.

You may be able to eliminate your wheel hop easier and cheaper with adjustable shocks. Have you tried that? Do you have a stock rear spring spring?

80Baby

Some time ago there was a thread started up about poly bushings that were crumpling while in service. That caught my attention because I swapped over to poly throughout. I believe it had something to do with quality issues, aka. being made in that big country overseas that makes things on the cheap. So when my car is back on the road, I'll get underneath it before every driving season and get the bushings. As for the diff, I went poly there as well.

leadfoot4

I bought most of the poly bushings that VB&P offered for C-3s, back in the mid 90s, when I went through the suspension of the '79 that my wife used to have. I can't report on longevity, as we sold the car about 4 years after I did all that work, but the additional "crispness" in handling was appreciated.

bbeck

Thanks for the input guys! I was getting a lot of walking/sloppy travel from the rear suspension last year before I sheared the bolts off in my halfshaft flange on the passenger side. I got lucky and didn't do any serious damage- but this is what gave me even more reason to focus on this area next. I tore into my rear suspension this past weekend and will have the diff out this coming weekend. I'm leaning towards the following:

1. heim joint strut rods
2. poly for the spring bushings (360 lb fiberglass mono)
3. new rear shocks (to better match the aftermarket spring)
4. rear crossmember bushings (solid or insert)

My trailing arm bushings appear to be in good shape still and probably recently replaced (mileage wise). While everything is out, it will get a good cleaning and some paint. I'll also check the u-joints and the rear diff/stubs for slop.

Can someone tell me the allowable tolerances for the axle stub play?
Any suggestions for better matching rear shocks? It currently bounces a decent amount and needs more dampening.

jb78L-82

I have been told by many that are very knowledgeable as well as professional rebuilders of the trailing arms that rubber is better in that location due to the rotational movement of that part-I have rubber.

With that stated, I have had poly cushings on the 360 mono spring since 1986-they look great today. Poly mounting bushings on the factory style rear sway bar-3/4 inch. Bilstein Sports. I strongly recommend heim joint competition struts-no bushings. I do have poly upper and lower front control arm bushings and they are terrific eliminating front suspension slop…Hope that helps!

SteveTheCorvette

As far as shocks go: I think the two best are the Bilsteins and KYB Gas-Adjusts. I picked up the KYB Gas adjusts on Rockauto for pretty cheap and I love 'em. I can't attest to how they'll work with the composite spring, though.

bbeck

Is there a rep on here for VBP? I'll probably order some stuff through them and I know that I saw a discount available to forum members at one time. I took tomorrow off to take the rest of the rear out and start cleaning/painting.