Poly or rubber
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Joined: Sep 2022
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Poly or rubber
In the process of ordering new parts for my 1978. Just had a 383 crate motor dropped in and need up upgrade the rear(99% it’s never been done)
so my question is what’s the pros or cons of going with poly over rubber? I’m not tracking the car it’s a 3rd car for fun. Just looking at what’s the best choice.
any help would be great as when I talk to parts guys I get the feeling it’s what they have over what’s best
so my question is what’s the pros or cons of going with poly over rubber? I’m not tracking the car it’s a 3rd car for fun. Just looking at what’s the best choice.
any help would be great as when I talk to parts guys I get the feeling it’s what they have over what’s best
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From: Virginia
In the rear?
Trailing arms: Rubber (I had Bairs do mine). This is a complex motion, and it will destroy poly bushings. You could also use a Johnny Joint in this location, but that's really expensive. These are the only rubber bushings in my car.
Strut rods: Heim Joints! I can't stress this enough. Nothing makes your car feel loose worse than bad strut rod bushings, and that includes rubber. It's also a complex motion that will destroy poly bushings. So eliminate them! They won't feel harsh, your car will feel a lot better, and will keep its camber adjustment since it eliminates the stock eccentric camber bolts.
Shocks, sway bar ends, and spring bolt cushions: All Energy Suspension poly bushings.
Trailing arms: Rubber (I had Bairs do mine). This is a complex motion, and it will destroy poly bushings. You could also use a Johnny Joint in this location, but that's really expensive. These are the only rubber bushings in my car.
Strut rods: Heim Joints! I can't stress this enough. Nothing makes your car feel loose worse than bad strut rod bushings, and that includes rubber. It's also a complex motion that will destroy poly bushings. So eliminate them! They won't feel harsh, your car will feel a lot better, and will keep its camber adjustment since it eliminates the stock eccentric camber bolts.
Shocks, sway bar ends, and spring bolt cushions: All Energy Suspension poly bushings.
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Ya know I don't often agree with Bikespace. But this time he's spot on! Wouldn't change a thing from the above recommendation.
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From: Virginia
Strut rods and the trailing arm are exactly where poly should not be used.
When used correctly (and made by Energy Suspension, and perhaps some others), they last. I can show you a car still driving around that has Energy Suspension bushings installed, by me, 20 years ago.
BTW, here's the fix for anyone cursed with a set of poly adjustable strut rods.
https://www.corvetteforum.com/forums...heim-ends.html
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My car came with those awful eccentric adjusters that are a bugger to tighten down without them moving.
So, back in the late 80's or early 90's I put in adjustable strut rods with poly bushings. About 2 years ago I converted those strut rods to heim joints. Just because I could.
The poly bushings were a little squished. But overall just fine and I could have kept running them, soooo,
It all comes down to whose poly bushings you run.
I've had extremely good luck with Energy Suspension brand bushings. And I have them all over the car.
So, back in the late 80's or early 90's I put in adjustable strut rods with poly bushings. About 2 years ago I converted those strut rods to heim joints. Just because I could.
The poly bushings were a little squished. But overall just fine and I could have kept running them, soooo,
It all comes down to whose poly bushings you run.
I've had extremely good luck with Energy Suspension brand bushings. And I have them all over the car.
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I had bad luck with energy suspension poly trans mounts. Yes, I know we're talking about strut rods but the 4 speed mounts they sold were fine for everything but the corvette. I called them at the time to see if I just had a bad part, but the tech told me they wouldn't work on a vette, different dimension. Yet that were advertised for the corvette??
A couple of years ago I got in a set of TA, new- never installed on a car but 15 or so years old. They were poly and sold back in the day when it was the rage to rethink the GM engineering dept to use poly. I merely tapped them, and they shattered like glass.
Now the bushings Tom's used were what I call a poly blend and never did that. 1000's were sold and I have never heard from anyone that they failed. They are somewhat pliable, but they are also only for Tom's arms since the OD is not the same as stock.
The TA's I just built have aluminum bushings, they are Van Steel arms and a good product.
A couple of years ago I got in a set of TA, new- never installed on a car but 15 or so years old. They were poly and sold back in the day when it was the rage to rethink the GM engineering dept to use poly. I merely tapped them, and they shattered like glass.
Now the bushings Tom's used were what I call a poly blend and never did that. 1000's were sold and I have never heard from anyone that they failed. They are somewhat pliable, but they are also only for Tom's arms since the OD is not the same as stock.
The TA's I just built have aluminum bushings, they are Van Steel arms and a good product.
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My exhaust actually touches the strut rods when the rear end is up on jackstands and suspension is hanging. But over 20 years I ran poly with zero issues. When the car is on the ground there is a fair amount of clearance. And the pipes run over the rod itself, not really that close to the bushing on the end.
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For unbiased Info I would call Dan at Vansteel, he sells Rubber, Poly, and spherical bushings.
Many would be surprised he recommends Poly over rubber and will tell you Poly offered today is not the same chemical compound as it was several years ago.
Many would be surprised he recommends Poly over rubber and will tell you Poly offered today is not the same chemical compound as it was several years ago.
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I wonder if poly went through a period of "gotta jump on the sales bandwagon" in the early 2000s to 2015s such that material quality was compromised. I put poly a-arm bushings in my '72 way back in the early-'90s and they are still there, looking fine. They do squeak a small bit, but otherwise are OK.
Team Owner
Joined: Feb 1999
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From: Republic of Texas
I wonder if poly went through a period of "gotta jump on the sales bandwagon" in the early 2000s to 2015s such that material quality was compromised. I put poly a-arm bushings in my '72 way back in the early-'90s and they are still there, looking fine. They do squeak a small bit, but otherwise are OK.
Absolutely, he mentioned the more firm and brittle compound poly that was used for the last 15 or so years. Many of us, myself included, switched to poly in the early 2000s that Vette Brakes and Parts (VBP) used that failed on us. I called VanSteele to order the rubber to replace the TA bushings and he talked me out of it, and said to go with a poly. He mentioned the poly used today is more forgiving and softer like rubber. Dan also said he has not had any complaints/returns/ failures in 5yrs+ of selling the poly with a new compound.
Having had both compounds of poly, the new compound is much more softer and forgiving like rubber compared to the firmness in the previous compound.