ya the BOSS 290's are 5.4litre, but before those came along they used a 5.6 that was based on the 302 block. they had a video of them building the motors and it looked really impressive, billet rods and pistons, and they were each dynod at the factory. i was wondering if it was a 347, cause thats around 5.6, considering the chevy 350/346 motors are called 5.7litres. ugh it would make life so much easier if we would just either pick metric or pick standard.