Complex sentence: The first complete V12 engine was built in 1941, designed by a team led by Harry Wood with Eddie Gass as the Chief Designer and in bench-testing it produced 1400 hp. There were problems with vibration and the cooling of the pistons and sleeves.
Split into simpler sentences: The first complete V12 engine was built in 1941, designed by a team led by Harry Wood with Eddie Gass as the Chief Designer. In bench-testing it produced; however, there were problems with vibration and the cooling of the pistons and sleeves.