From my understanding, steel can handle almost unlimited stress so long as the forces applied are below the point of failure. Aluminum on the other hand will eventually fail after such repeated stresses.

Currently I have poly/rod end Spohn LCA's and PHR. In the future I plan to change over to dual rod-ended components and I'm wondering (at least on paper) how aluminum components like those made by LG Motorsports would stand up.

I imagine that actual handling and performance gains are not very noticeable between steel and aluminum, but how about strength and longevity?

 

1. Suspension Tech Pete
2. Per JonA's page http://www.jonaadland.com/Z28/Mods/L...minumLCAs.html

Similar enough that, it should give you some idea of the forces that they can handle.

 

There is some very good info in 1LEThumper's link.

Not to worry about the durability of 6061-T651 aluminum control arms, as long as they are of sufficient size. Many producton cars, including Corvette use aluminum control arms and knucles. Some are forged, some are cast. Some aftermarket steel ones are definitely overkill and overheavy. Bigger isn't always better or necessary, but it is usually more visible. Bling, bling!

I wouldn't have a problem with LGs. As the link said, rod ends can be the weak link. Getting road grime into them just acts like grinding compound on the closefitting parts. Personally, for a street car I'd probably use a stiff rubber bushing at the axle end and a large spherical bearing at the chassis end. Most of the compliance would be eliminated, with just enough to limit the noise and harshness to the chassis. It takes a little more fabrication like welding on a cross tube, and machining the inner spacer, but you can use a larger bearing with enormous strength and fully seal it from the elements. If I knew how to post a sketch I would.

 

Why not the reverse (rod end on the axle end) - simply to cut down on noise?

Chris

 

Good question.

The chassis end may be more protected from the road grime. That's the basic reason. It depends on the vehicle. With a 4-link upper front mounts are very well protected. I don't think there would be a lot of difference which end was which for NVH. Oh, yeah, spherical bearing end would probably be a little heavier. No big deal.

 

Good point - I never really checked it out (installed mine with the rod end on the axle side - just went with the general "consensus" that this would be quieter - poly on the chassis side. I can say that the rest of the car (exhaust, etc.) is at a higher volume threshold that I couldn't detect and sound difference between the 1 rod end and my previous poly-poly.

The rod ends that came with the bmr lca's were total crap - I replaced them with some NMB/NHBB spherical bearings - I check them out every couple of months and after about a year they still look great (clean and lube them when I check them though)

But good point, if there is no noise difference the body mount would probably be better - either way though it would be trivial to make a shield for the rod end, I may do that now.


Chris

 

LG's come with dust boots on the rod ends now...so no worries. I've almost completely eliminated every bushing on the car and replaced it with a rod end and I drive it on the street, not so much anymore since the motor project, but it used to be driven in all kinds of weather and with a good rod end like a QA1 even with out a dust boot they can last for years before they start to make a lot of noise. Some of my friends down in Texas have been running them with the dust boots for a long time and have had no problems at all. So don't let rod ends scare you.

We're not building Caddy's here people.