V engine
A supercharged Northstar was used in the 2006 Cadillac STS-V and Cadillac XLR-V. The bore was reduced for increased strength and improved head gasket sealing. Variable valve timing is used on both the intake and exhaust sides. The STS-V engine produces at 6400 rpm and at 3900 rpm with 9.0:1 compression and the XLR-V engine produces at 6400 rpm and at 3900 rpm.