Polyurethane Bushings

[97CobraLSC]

Today I bought the following from Bill @ SCP:

Outer Knuckle bushings POLY
Inner upper control arm bushings
Inner lower control arm bushings UHWM
Pair of toe compensators
Front differential bushings POLY

He was great in helping me figure out just what I needed to make the rear end better.

Since the car I bought from GMAN / gtshaw has ~215k miles on it, it's time to do a complete overhaul.

I'll be buying the aluminum subframe bushings once I have more money to put into the car.

Thoughts on the poly vs delrin?

 

[beerdog]

I would say it gets into the quality of the poly or delrin. Some people have reported the rear poly bushings you speak of prematurely failing. The only person who was really making the delrin bushings was Doug. Have not really heard of anyone reporting delrin failures. BEst thing to compare the 2 would be to get exact material specs and then compare parameters such tensil strength, compressive strength, etc. There are many grades and quality levels of both plastics.

 

[97CobraLSC]

I would say it gets into the quality of the poly or delrin. Some people have reported the rear poly bushings you speak of prematurely failing. The only person who was really making the delrin bushings was Doug. Have not really heard of anyone reporting delrin failures. BEst thing to compare the 2 would be to get exact material specs and then compare parameters such tensil strength, compressive strength, etc. There are many grades and quality levels of both plastics.

True. I guess these can't be worse than what is on the car now. It's hard to narrow down the noise(s) on the car, so I'm just replacing everything.

 

[beerdog]

As far as noise, the OEM stuff is going to be the best. The performance bushings just make it noisier. Those aluminum sub-frame bushings will make the ride much much harsher.

 

[Lvnmarks]

Today I bought the following from Bill @ SCP:
Front differential bushings POLY

I bought a set 9 years ago from MN12 performance and within 6 months one of them shattered. Went back to a stock bushing after that. I think it may have been a freak occurrence but FYI.

 

[97CobraLSC]

As far as noise, the OEM stuff is going to be the best. The performance bushings just make it noisier. Those aluminum sub-frame bushings will make the ride much much harsher.

Ha, if you heard the car right now, you wouldn't think OEM was quiet. It's terribly neglected, so these should help.

And as far as the subframe bushings, I'm coming from a car with coilovers that has a very, very harsh ride, so it can't be too bad.

I bought a set 9 years ago from MN12 performance and within 6 months one of them shattered. Went back to a stock bushing after that. I think it may have been a freak occurrence but FYI.

I hope I don't have that problem, but only time will tell.

 

[chris2523]

The only person who was really making the delrin bushings was Doug.

delrin rear control arm bushings are back in production by 1 person so far, and possibly a 2nd person in the future. probably some of his other stuff will come back as well.

 

[97CobraLSC]

delrin rear control arm bushings are back in production by 1 person so far, and possibly a 2nd person in the future. probably some of his other stuff will come back as well.

I saw that, but unfortunately, I cannot wait for those to be produced. I might try to get the subframe bushings when they're available, but otherwise, the poly and UHWM will work.

 

[Bill Evanoff]

Comment on "Harshness"

As far as noise, the OEM stuff is going to be the best. The performance bushings just make it noisier. Those aluminum sub-frame bushings will make the ride much much harsher.

One would think so, but our beta test cars all experienced only a minor increase in the ride harshness. Most tagged it approx. 10% harsher. Since we have gone into production with these I've yet to hear a complaint about this potential issue from the dozens of customers with these installed.

I agree that one would not buy these solid subframe bushings unless they were looking for a performance (handling) improvement or had a very powerful engine and were looking to control the entire rear end movement. Both of these type customers likely are willing to accept the increase in stiffness.

Keep in mind that the entire front suspension is held to the body of the car with only a few bolts. There are no front subframe bushings at all, but there are numerous suspension bushings up there to soften things up. The same would apply to the rear suspension component bushings after one installs the very rigid solid AL bushings.