[mattpatt]

Just to add some more info to this thread: I have SP3033 (about 400 miles on it so far). It had a mild steering wheel shake at ~62 - 67 mph. Based on this thread I had the R/T ball joints installed by Erick Voss. He also did the needed re-alignment and re-balanced the wheels (all 4) on the car and adjusted the rack & pinion clearance. The shake has been reduced noticeably but not completely (seems to be ~63 - 65 mph). On some roads it's gone, on others it's there. Erick noted that the SPF cobras are prone to shake when the bigger wheels, lower profile tires are used with a lighter front weight. In my case I have the 18" wheels, 255/35's on front and have an aluminum small block (probably the worst conditions for having the shake). Erick thought that a less stiff front spring rate might help. For now, I'm playing around a bit with tire pressure just to see.