Built through a collaboration between Boostline Performance and Journey HQ, this turn-key 427 LS package combines our proven Darton-sleeved aluminum block with carefully selected components to deliver serious performance and reliability. Featuring a 4.125" bore and 4.000" stroke, the 427 is a torque-hungry beast that excels in everything from street cars and trucks to dedicated performance builds. The large bore allows for high-flow cylinder heads and exceptional power potential, making this combination a favorite for both naturally aspirated and power-adder applications. Designed as a complete, ready-to-run package, it delivers the performance you're after without the guesswork.

Build Specs:

• Seasoned GM Aluminum 5.3L Gen 4 Block with Darton Sleeves
• Blocks are CNC Decked, CNC Bored and CNC Torque Plate Honed
• Block Cerakoted Chevy Orange
• BTR Crankshaft with welded reluctor wheel
• BTR Connecting Rods
• Mahle Forged 2618 Pistons and Ring Set with heavy wall wrist pins (Flat top unless otherwise requested)
• ARP Main Studs
• ACL Main & Rod Bearings
• Durabond Cam Bearings
• LS7 Lifters
• Improved Racing Crank Scraper and Windage Tray
• New block plug kit and barbell
• BTR Trinity Intake Manifold with Fuel Rails
• Holley 302-1 Oil Pan
• DW Injectors
• BTR Stage 4 LS7 Camshaft
• 821/823 Heads, remanufactured - New springs & seals
• Pushrods, one piece - hardened, 7.400”
• GM Rockers with BTR trunnion kits installed
• High Volume Oil Pump
• ARP Heads Studs
• Cometic Gaskets
• Boostline Valve Covers
• GM stock front cover
• GM stock valley cover
• GM stock rear seal housing
• TR6 NGK Spark Plugs
• Granatelli 102mm Gen 4 Drive by Wire Throttle Body
• ATI Damper
• Holley Terminator X Max with Drive by Wire and 4l60/4l80 Transmission control