The Boostline Performance BL327JLB street series 5.7 long block is the logical next step up for any vehicle that originally came with a 5.3 LS. We utilize the same 5.3 core and bore the block to 3.898 in. and use a forged flat top LS1 piston. Taking the bore from 3.780 in. to 3.898 in. really wakes up the platform. This engine is a good choice to replace or upgrade that tired stock 5.3 in your ride. Whether you are wanting stock idle for momma's grocery getter or some nasty chop for the hot rod, this long block build can get you there on a budget.

Boostline Performance BL327JLB Specs:

• GM Iron 5.3 Block
• Blocks are CNC Decked, CNC Bored and CNC Torque Plate Honed and Align Honed
• Stock Gen IV 5.3L Crankshaft
• Stock Gen IV Connecting Rods with ARP bolts
• Forged 2618 Flat Top Pistons
• Cathedral Port LS1-Style Cylinder Heads
• Hydraulic Roller Camshaft:
  • Duration @ .050 in. 21x Intake/22x Exhaust
  • Lift: .57x Intake/.57x Exhaust
  • Note: Camshaft duration and lift values are shown with the final digit omitted to protect proprietary camshaft profiles. Boostline Performance uses lobe designs developed for this engine, and its intended performance range and operating characteristics
• LS7 Lifters and Trays
• Single roller Billet Gear, performance, timing chain & gear set
• Pushrods, one-piece - hardened, 3/8 in.
• GM Rockers built with bronze bushing-style trunnion kits
• New Rocker Arm Bolts
• ACL Main & Rod Bearings
• Durabond Cam Bearings
• New block plug kit and barbell
• Melling High Volume Oil Pump
• ARP Main Studs
• ARP Head Studs
• Fel Pro Gaskets Throughout
• BTR small bore LS9 head gaskets - 3.950 in. bore
• Boostline Valve Covers with coil mounts
• GM muscle car oil pan and pickup tube
• GM stock front cover
• GM stock rear seal housing

Boostline Performance BL327JLB Features:

• Fully assembled long block engine
• Includes cylinder heads and valvetrain components
• Professionally assembled for street and street-strip performance applications

Emissions Note:

This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART