I didn't box mine at all. But then again, I'm just running a 350. If anyone has actually experienced any twisting of their frame from Torque, let me know. I wonder about that.
Would boxing the frame be stiffer than a lighter weight option, such as "X-ing" the frame with tubing?


52 GMC 3/4 ton pickup
68 Big Block Vette
68 455 Firebird