Something's wrong here. Both have the same stroke but cyclinder 2 is smaller than cyclinder 1. No way they could have the same displacement.A Atwood said:Cyl #1- 4" bore 3" stroke =37.7ci
Cyl #2- 3.465 bore 3" stroke = 37.72ci
V= pi x r^2 x h
cylinder 1 = 3.1417 x 4 x 3 = 37.7 ci
cylinder 2 = 3.1417 x (3.465/2)^2 x 3 = 28.29 ci