pontiac g8 st sema concept 001
The new LSX454 crate engine displaces 7.4L and produces 638hp (476kW)Enlarge Photo
The LSX454 (part number 19166972) measures 7.4L in displacement and is rated at 638hp (476kW) and 600lb-ft (813Nm) of torque, which means the naturally aspirated mill almost matches the 638hp (476kW) and 819Nm (604lb-ft) of torque from the supercharged LS9 found in the Corvette ZR1 supercar.
The new engine is built on the same LS9 cylinder block but features new six-bolt LSX cylinder heads and a forged rotating assembly. Interestingly, GM is offering the ZR1 mill as a crate engine as well. The standard G8 GXP, meanwhile, features a 6.2L V8 engine rated at 415hp (309kW) and 415lb-ft (562Nm) of torque.
In addition to the LSX454, the SEMA G8 GXP comes with a standard Hydra-Matic 6L80 six-speed automatic transmission, a lowered ride height, stiffer springs, and the same brake package from the Cadillac CTS-V. Other details include 20in aluminum wheels with a black chrome finish, a custom bodykit, and sports exhaust system.