one other thing though is the mains on a V-block are wider (more surface area) than a inline. (at least the ones Ive seen. I-6’s are tough though, Ive had 2 amc 6’s a 232 in a concord (newer version of the hornet) and a 258 in a CJ7 jeep. Dad had a ‘74 2wd F250 with the 300, np235 3.73’s, It was a awesome truck! Id think if all 4/6/8 cyls fired at once it would vibrate like hell & destroy itself quickly. Jd 2cyls? Quite the tourque monsters, A ‘49 jd “A” is 321 cubic inches, less than 1,000 rpm top speed, 5.50 bore x 6.75 stroke. That tractor would just pull all day long & at night youd see a 2” flame out the top of the exhaust. A “G” was bigger yet, never drove one-wanted to. Id hate to feed one though, especially at todays fuel prices. Love that sound though. You can work them so low in rpm you hear the magneto snap over.