The LS3 427 SS is based around GM’s new Gen IV 4.065 aluminum block. The LS3 designation has a Mast Motorsports engineered camshaft that is custom ground on a Mast Motorsports LS7 cam core. The camshaft is designed with a narrower lobe separation angle to produce high RPM horsepower for the customer wanting a Street/Strip combination. The 427 foundation is a honed and decked LS3 aluminum block with a forged Scat rotating assembly with forged Mahle pistons that is topped off with Mast CNC LS3 heads and a LS3 intake manifold. ARP fasteners are used throughout and Manley pushrods ride on LS3 hydraulic roller lifters. The 427 displacement uses a combination of a 4.070” finished bore with a 4.100” stroker crankshaft. The custom Mahle pistons are specifically designed to reduce cylinder wall wear and reduce the oil consumption that is typical for GM Gen IV stroker engines.