CapriRacer -
Thank you for posting that. My information was vague. I was able to get tires rated at 51 PSI, so that's my max. Because passenger tire valve stems are rated at 65 PSI (according to that
PDF I cite in my previous post), I should be fine.
For additional safety, the next time I get a set of (51 PSI rated) tires, I will make sure they install the valves you cite. If they don't have them, I will get some myself.
CarloSW2