Delrin Bushings

[Dtangard]

Quick Question

Are delrin bushings worth the money over polyurethane or mazdacomp bushings? My car is progressing towards being a track only car and is due for some fresh bushings. I read delrin is stiffer than urethane and is also self lubricating. Is the life expectancy greater for delrin?

[savage217]

It really depends on the application. I run delrin front control arm bushings and Urethane bushings in other areas. Urethane still has some flex to it. Delrin has almost no flexability. My experience with delrin front control arm bushings has been positive. I chose them for that application because there really is no need for the bushing to be flexibile in that area. However, on the e36, running delrin rear trailing arm bushings, is a bad idea. That bushings needs to have some play side to side because of the geometry. Delrin trailing arm bushings have been none to cause more harm than good in that area. Moral of the story, it depends on where the delring will be used on your suspension.

[WillM]

If it were me, I'd go with the MazdaComp suspension bushings.

Delrin or Urethane will be stiffer, but require maintenance. The MazdaComp bushings are maintenance free and they retain the magic bushings that Mazda designed into the Miata. Mazda placed slightly softer bushings on one (or two, I forget) of the points on the rear lower arms. I believe they are the front inner bushings (on the rear lower arms). The slightly softer bushings allow the car to toe in a bit under braking, which assists stability. I believe the MazdaComp bushings, while proportionally stiffer, also have the same feature. Note: This means it is important to put the right bushings in the right location...! Several look the same, but they are not.

I had the ISC setup, which uses delrin for some bushings and solid bushings (spherical bearings) on others. Proper maintenance required taking the arms off of the car twice a year, cleaning out the crap, apply lube, and reinstall...which meant re-align too. This was on a track-only car. A car driven on the street would be even worse. Before maintenance, when the lube had been invaded by road grime, it was impossible to move the suspension components by hand. I installed zerk fittings at one point, and though they helped, they helped a bit but didn't solve the problem. All of that said, when the bushings were freshened, the arms moved very fluidly - it was pretty awesome. With the shock removed, it is almost effortless to move the arms up and down by hand.

The down side of the MC bushings is that they are expensive. Also, similar to the stock rubber-bonded bushings, you have to be sure to not tighten down the arms until the car is on its wheels, but any good alignment shop would know that.

If you have extra money to spend on bushings alone, NoPro in japan makes an awesome set of fully sealed maintenance-free spherical bearings.

I'd suggest the MC bushings. If you are on a budget, I guess the powerflex bushings are your choice...but they are NOT maintenance free.

[Tim Mahoney]

I got the ISC Delrin front uppers to dial in some more camber @ streetable ride height. I'm on the 3rd season and have put about 14K miles on them. They do get creaky but the zerks supplied with the kit do an adequate job of delivering the grease where & when it's needed. A little more maintenance than rubber or poly, but worth it if you can't get enough camber with concentric bushings.

[WillM]

Tim - that's a great point.

Those offset bushings are my only exception - I have 'em on my car.

[Dtangard]

Ok guys thanks for the info. It sounds like a combination of delrin uppers and Mazda motorsports bushings are the best option.