Math:
2.25 (diameter)
1.125 (rod size)
8 (stoke)
pi= 3.14
Volume = stroke * pi * ((diameter/2)^2)
Cylinder volume - rod volume = fluid volume (total displacement)
Cylinder volume = 8*3.14*((2.25/2)^2)=31.79 in^3
Rod volume = 8*3.14*((1.125/2)^2)=7.95 in^3
Total displacement = 31.79-7.95 = 23.84 in^3
Total displacement / desired turns lock-lock = 23.84/2.5 = 9.5
So you'd need a ~9.5 cubic inch valve to get 2.5 turns lock-lock.
I have a Trail-Gear ram that is the same size, and a 9.8 cubic inch valve. I like it. Much better than the ~3.75 turns of the stock box
