KW Suspension Salt Spray Test
In March of 2004, KW made the changeover of its complete production of its Coilovers to the new reference standard Inox Line. This proved to be quite an undertaking, requiring a huge amount of resources involving a multitude of changes and investments. The first kits rolled out of assembly in late 2000, and it was clear that this was truly a milestone event. Even with the known corrosion resistance characteristics of the new housings, not even the experts could have predicted the extreme results that would come of the harsh testing to come.
A more extensive test was performed to DIN 50021 SS standards at Chrom Schall, in Simaringendorf, to document the impressively high level of corrosion resistance of the Inox line vs. the competitions galvanized units available on the market today. Coilovers from six different manufactures were compared in the 480-hour Salt spray testing.
During the testing, the samples were inspected at pre assigned intervals of 48 hours, 150 hours, 336 hours and 408 hours to document the progression of the corrosion of the Coilover kits. Included in the samples were an original KW galvanized housing, for comparative testing for our past products and customers.
The struts were sprayed in a controlled chamber with salt water for 480 hours, which corresponds with two average winters in an average four-season climate, representing approximately 30,000KM of road use. After only 48 hours, the first signs of rust showed up on all of the galvanized systems, in the threads, clamps, and mounting points.
After 150 hours, the results shown were even more dramatic. Blisters of red rust appeared on all of the Supersport premium threads, as well as many of the other systems. After 480 hours of testing, the differences on all the systems were clear. The KW Inox line Coilovers were completely unaffected by the test, looking no different then when the test began, but the same could not be said for the galvanized systems.
Not surprisingly, there were measurable differences in quality between the different manufacturers of the galvanized systems. The original galvanized KW Coilovers faired quite well, and with some work could be cleaned and used, and the Bilstein system did not corrode as much as the other tested systems. The test results showed rather impressively how the Inox stainless steel technology increases the purpose and value of the investment in a height adjustable Coilover system, providing a lifetime of adjustability for the enthusiast.
The testing confirmed what most manufacturers and customers choose not to think about, that a Coilover system that cannot be adjusted after one winter is not a sound investment. KW has now set the technological bar that all other systems are to be judged against.