So I was doing some reading on the differences between the 1199 and 1299 engine and it looks like the 1199 and 1299 cylinders are essentially the same, same valve sizes, same valve lift. Only thing I could find is there are minor contour changes to the combustion chamber to take advantage of the modified squish area. It looks like they should be interchangeable. Anyone know if this is true? Part numbers have a different letter designation.