There is a perfect pressure to run for every vehicle. But what that pressure is depends on many, many factors including tire construction, tire materials, road surface, road conditions, temperature, driving style, vehicle weight, suspension set up, wheel type, wheel size, desired ride quality, etc, etc, etc. I run 30/30 on my '65 B, 29/31 in the '58, and 30/32 in the '67. Sometimes I take it down one or two PSI. It just depends on which of the aforementioned factors are most important at that particular time.