You could well be right. That's a good point. I think they are really close in strength. But still the 9 inch is cheaper to build......unless you find a good dude like Roy that will sell them fair. I was real fortunate with the 9 inch I have. One of my customers at work just walked up and said "Hey Rusty, you want a Ford 9 inch for free? Come get" so I did. LOL