Factory Magnum Heads

They make more port velocity and stronger low lift flows while the high lift flows are within a couple of cfms when done the same. The 2.02's really help in the upper RPM ranges above 6500 rpm's, so if your build is going to be turned this high then I may give them consideration, but if most of your driving is going to be at a lower rpm than this then I would stay with the smaller 1.88 valves. As you'll have more Tq and power due to better port velocity.