Tutter

Hi all,
I recently picked up a set of elephant racing polybronze bushings, direct from them. Almost immediately after unboxing them I found that they were extremely loose as for as bushings go. I broke out the calipers and took many measurements (ill attach a few images). All four bushings measured the near the same.

Measurements as follows
Bronze bushing ID 2.100"
Steel sleeve OD 2.092"

Total of .008" over, or .004" per side of clearance.

I do have a fare amount of experience with bushings and this much tolerance would be considered worn out. A proper fit, greased, at this diameter would be .002" over, maybe even less.
How this bushing is designed as is, all the actual load would have to be taken up by the beveled part of the bushing with some careful shimming of the spring plate cover. The beveled area is much smaller and doesn't get nearly as much grease as the barrel of the steel sleeve. I'm certain this would lead to accelerated wear/ considerable play, and the need to reshim the spring plate cover over time. All in all I'm not too impressed with the quality of the parts, given the price. I have reached out to Elephant Racing and they responded with its fine and the tolerance is for grease.

I'm interested to know if anyone else has noticed this, or has any info or experience on the long term wear or problems with these parts?

walfreyydo

Im not running these myself per-say (I went with Powerflex poly) but I do believe Elephant has a fairly good rep with these bushings and have been run in countless cars over the years. I would run them or if you arent comfortable, send them back and go with something else.

Also, I dont think you can measure tolerances that fine with a caliper (micrometer would be best)

Tutter

Sound advise Walfreyydo. Returning them is always an option. I really like the concept of the polybronze bushing, and the parts as is would certainly work. But strictly from a bushing design standpoint I think it could benefit both in performance and longevity of the bushing with a little more attention to this tolerance. For the price I would want excellent performance and longevity, and I hope others feel the same. Hopefully those who have had these bushings long term, or with engineering and manufacturing experience will chime in. I did reconfirm these measurements with my micrometer.

walfreyydo

I know with those they recommend you add zerk fittings to the torsion bar carrier so they can continually be re-greased. I wonder if there is something to what they are saying about the tolerance that loose for the grease? They do need to be maintained with more grease - thats part of why I didnt go with them (and the added NVH of any monoball/metal bushings). I have read that solid/monoball bushings do wear over time, increasing their tolerance and as a result, noise - another issue I wanted to avoid (as well as cost)

Have you seen those instructions?

FWIW I have been happy with the powerflex bushings (albeit no way to compare against a car with solid bushings) and my car is mainly for track/autox.

Tutter

I did go over all the installation documentation, all strait forward. Absolutely grease is required, and regular re-greasing is part of any bushing you want to keep running smoothly (something I don't mind doing) but .0015" or .002" total clearance is really all that is required for a light film of grease to properly lubricate a bushing. Anything more and the grease will only be sqeezed out as the bushing is loaded radially. NVH would be nice to keep to a minimum, and keeping everything tight is the only way to mitigate this. In reality this bushing should be as play free as a nice new monoball. I wouldn't run a new monoball that I could feel clicking back and forth that's for sure. I will definitely be keeping full Poly over the Polybronze as an option if I cant resolve this with ER or on my own, sounds like most are pretty happy with Poly in this application.