Fifth-Gen Camaro SS Endlinks - Stress Test
Stronger Endlinks for Camaros that Like to Turn Hard
From the June, 2012 issue of Camaro Performers
By Steven Rupp
Photography by The Author
1. Here’s the Pro-Rigid link...
1. Here’s the Pro-Rigid link kit from Proven Wicked. The 12mm XM-style forged 4340 chromoly rod ends (with injection molded Teflon/Kevlar liners) used are not commercially available parts, but were instead custom-designed specifically for this application. The fronts are longer as to easily clear the strut flanges and are extra thick for increased stiffness. The rears are shorter to allow the use of two males with an adjustment collar for on-car changes in length.
When GM launched the new fifth-gen Camaro SS we got a hell of a car. But the engineers didn’t give us a track car, a lowered car, or a car optimized for performance. What we were presented with, in stock form, was a modern muscle car designed for the masses. And let’s face it; the masses don’t generally push their cars hard. Thanks to the aftermarket, we can take the new Camaro to places the engineers at GM weren’t allowed to go.
A car is a system of parts all moving and grooving together in a mechanical tango. Change one part and the effect can ripple throughout the car. Add a blower … smoke the stock clutch. Mount up sticky tires and you’ll most likely launch an axle into orbit. It’s hot rodding, and often changing one part necessitates another. One example is sway bars. The stock Camaro rolls like a ship at sea, and the quickest fix is some stiffer bars, but oftentimes the stock endlinks suffer under the added strain.
Shane Wagner of Proven Wicked saw this problem and engineered a solution with his Pro-Rigid endlinks. Now, an endlink may seem like an easily engineered item, but there’s more to it than you might think. As Shane explained, “The GM specification for the endlinks is to have a minimum of 52 degrees of total stud misalignment in the front and 50 degrees in the rear. Most rod ends with a bolt through them don’t even come close to meeting this specification. For example, a standard M12 rod end is around 26-28 degrees.” When they run out of travel, they bind. This is even more problematic in the front of the car since the links are attached to the struts, which move when the car is turned, and a bound-up link can cause steering resistance until the link unbinds or breaks. Since these links are adjustable, they can be orientated perfectly when the car is lowered, which changes the suspension geometry. As a bonus, they look pretty sweet.
2. Closer inspection shows...
2. Closer inspection shows some pretty trick hardware in use, like the mil-spec locking keyway washers. These ensure that the rod ends are always clocked in perfect relation with each other before the jamb nuts can be locked down. The custom U-nut locknuts also offer superior vibration and heat resistance compared to nylon insert nuts. After all, if a link fails in a hard turn, your day could get bad, really fast.
3. To get the rears adjusted,...
3. To get the rears adjusted, we simply matched them up to the stockers and locked down the jamb nuts. It’s pretty easy to see why the new links are so much stronger than the stockers.
4. For extra peace of mind,...
4. For extra peace of mind, the links incorporate a safety wire tab to use in conjunction with the pre-drilled jamb nuts. Hey, if it’s good enough for the aircraft industry, it’s good enough for a Camaro. The adjustment sleeves are machined from 7075-T6 billet aluminum and Type III hard anodized red for corrosion resistance. They come tapped for left- and right-hand threads, which allow for on-car adjustments.
5. Installation is simple....
5. Installation is simple. After getting the links close in length by matching them to the stockers, we bolted them to the car and then to the bar. If the length is spot on, and you don’t want to pre-load the bar, then the second link should easily slide into the sway bar hole. Pre-loading the bar is handy for tuning the car to drive on tracks that have predominantly left- or right-hand turns.
6. In addition to setting...
6. In addition to setting pre-loads, the adjustability is also good for removing acute angles to the sway bar. This is common on lowered cars or aftermarket sway bars with multiple holes for changing the rate of the bar. By making sure the link is as perpendicular to the sway bar as possible we can ensure there won’t be any bind.
7. Proven Wicked didn’t use...
7. Proven Wicked didn’t use guesswork and a magic wand to come up with their endlinks, they used science. Running finite element analysis (FEA) simulations you can see the difference between the OE links and the Pro-Rigid pieces. The ghosted gray image is the static non-loaded position; the red is the highest stress zones, and the blue signifies the lowest. Under high load, the stock endlink flexes, thus reducing the bar’s effective rate. Since the Pro-Rigid links are over seven-times stronger, they don’t flex, and the sway bar exerts its proper and consistent force. Also, this test was done with a stock bar. Larger aftermarket bars would cause the OE link to deform even sooner, and to a greater degree.