Type: LS7 7.0L
Displacement: 427 Cubic Inches
Compression Ratio: 11.4:1
Bore x Stroke: 4.125 x 4.000
Rev Limit: 7250 RPM
Crank: Callies Forged
Rods: Callies H-Beam
Pistons: Mahle Motorsports
Cam: Mast Custom 3-Bolt Core Cam
Heads: Mast Black Label LS7 285 Heads
Intake: GM LS7
Valve Springs: Mast Premium Dual Springs
*All hp numbers will be within 2% of the advertised number.
The LS7 HO’s heart and soul is the new GM Performance LS7 aluminum block. This LS7 engine family utilizes a Mast Motorsports-engineered camshaft that is custom ground on a Mast Motorsports 3 bolt cam core. The 427 HO’s foundation is a fully machined aluminum block with a forged Callies rotating assembly with Mahle pistons that is topped off with Mast Motorsports Black Label LS7 285cc cylinder heads and a LS7 intake manifold. ARP fasteners are used throughout and Mast Motorsports Black Label pushrods ride on GM LS7 hydraulic roller lifters. This hand built LS7 based engine utilizes a camshaft that has a moderate lope that creates great mid and high RPM power for the customer that will be aggressively racing their vehicle, but still wants great street manners for a daily driver.