BMR - Spherical bushing vs Poly bushing

11Shelby500

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I have the BMR upper control arm mount and upper control arm with the spherical bushing. The NVH is honestly too much even for a weekend car/track car. I like to drive my shelby with the windows down and no music but I still find the noise unbearable. Will I notice a significant difference in NVH if I replace the spherical bushing with the poly bushings? The rear end was already a little noisy before as I think its going to be on its way out soon with the rwhp I am putting down. Thanks in advance for your input.
 

mdoan

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Yes the poly bushings are substantially quieter. Even my speed shop said to use the poly’s and they’re nuts. Spherical are for race applications only.
 
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SCGallo2

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Both upper bushings are poly on my car with dual spherical rod end lowers, and it is tolerable as a weekend fun car. I could daily it if I had to. I would not install a spherical bushing on my upper unless it was a strip only car.
 

OldYeller

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I have the BMR upper/mount with Poly on mine, and the lowers are Poly as well. It picked up maybe the faintest increase in NVH over stock.
 

Catmonkey

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I've only had the rod end on the adjustable lowers and I used rubber rod end covers and I wouldn't say they were noisy, as in clanking, because the rubber did a good job of keeping the ball centered in socket. It did transmit some road noise, but I'm not sure it was worse than poly. I just found the ride a bit too harsh on a bad road surface. I'm sure the upper would transmit more road noise. I have BMR uppers and lowers with poly bushings on my car now and I don't find the NHV bad at all. The rear end is more controlled over rubber, but you give up a little ride comfort. The trade off was more than worth it for me. I still have rod ends on my watts link (Fays2) and I don't think they contribute any increased NHV.
 

11Shelby500

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Im going to give it a couple 100 miles before I change the spherical bushing to the poly. I may have already bought the poly upper control arm anyways lol. I need to build the rear end soon so I might wait till after I get it done to see if the NVH is more tolerable. Thanks for the input guys!
 

RBB

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I switched from a BMR UCA with a poly bushing to the spherical bushing a few years back. Don't really notice any difference in NVH between the two....I don't even notice the additional NVH at this point.
 

Corbic

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Polyurethane should never be used in a damn bushing. Absolutely the wrong product for that application.

Go full race car or keep the OEM rubber. Poly binds, squeaks and quickly falls apart.
 

802gt500

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Polyurethane should never be used in a damn bushing. Absolutely the wrong product for that application.

Go full race car or keep the OEM rubber. Poly binds, squeaks and quickly falls apart.
22k since poly bushings never a sweak or issue. Each to their own
 

Catmonkey

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All BRM bushings have a grease zerks, so they can be lubricated. Use synthetic grease to do that. I think mineral based grease will break down polyurethane over time. Rubber will start to dry rot due to ozone and oxidation from the time it's manufactured. Rod ends wear out due to use. Bushings are maintenance items.
 

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