Subframes...Round or Square?

[n20lx]

A round tube will load more uniform in all directions, but your still gonna have more moment of inertia with a square or retangular tube. As far as stress due to tension this will rely on cross sectional area. i still think you see round tube in roll bars from formablity than from strenghth since the difference between the loading in the variuous shapes is slight. you don't see round bridge beam, building columns or even connecting rods. i don't have my books at the house so I will do some calc's at work.