270 engines powered untold thousands of WW II military trucks- - - -there's no real reason to upsize the displacement. Since most of those engines were used, abused, and scrapped by dirt track racers and Bonneville land speed record attempts in the 1950's and 60's, there are very few engines and/or rebuilding parts still available. If the engine needs to be rebored due to cylinder wear, it might be more cost-effective to sleeve all six cylinders back to whatever bore size you have currently, and re-use your pistons. Piston rings are much more available than replacement pistons- - - -just "thinking outside the box!"
Jerry
