I'd like to fabricate my own rear lower control arms. There's a lot of choices narrow/wide ptfe lined etc. any input on what to use would be great. Thanks

 

Street, strip, road race, combination?

 

It's street with occasional strip and maybe some autocross thrown in.

 

If you don't want it to be too noisy, and if there is minimal off axis rotation (like a parallel 4 link, 3 link w/panhard, watts link etc.) you can run a greaseable poly bushing at the chassis end, and a greaseable spherical at the axle end. That will give you a little compliance and noise isolation for the street but still kick ass at the track. You have to have your geometry right, the poly will resist movement off axis and if you have something out of line you will start concentrating force into unintended places.

If you have any off-axis rotation (double triangulated 4 link for instance), or are willing to tolerate more noise in the car just run sphericals at both ends. Spherical will also be more tolerant of oopsies in the design, and are max performance. Whiteline makes some hybrid bearings that could work for you, but they are expensive, and wear items.

The bad thing about rod ends or Heim joints is you get into a lot more maintenance, and when they start to fail they rattle, the good thing about rod ends is that they are usually installed with circlips and easy to replace. Longevity won't be as good on a street car as a bushing, but they will perform better.

Generally the larger bearing you can fit the better, often space will dictate what you can actually install. Obviously your ends need to be at least as large as the tubing you are using. In most instances even an undersize spherical bearing is going to be much stronger than any other component in the link. Usually if you get a bearing somewhere close to the size of the OEM bushing you are in good shape. The wear life will be longer on a larger bearing, and you are spreading the force across a larger area on both the chassis and axle ends (the locations where you are putting in the mounting tabs will be further apart).

The easy button is to look at what's available in the aftermarket, find something that is well rated and mimic it. You can usually make something with excellent quality components for a lot less than the cost of the off the shelf part.

 

Thanks Ben. The FK AIN16 looks like it would fit and have a similar size to the factory bushing and they offer a wide bearing cup that's just right for 2x2 tubing. These are available with or without a ptfe liner. Would a ptfe lined bearing last for street duty?

 

I would go with PTFE, it's less maintenance and shouldn't attract dust like a greased steel on steel unit would.