SKU: BPMS4271LS
BluePrint Motorsports GM LS Compatible 427 c.i. Pro Series Engine - Power Adder - Long Block
$11,999.00
427 c.i. 610 Horsepower Long Block

Horsepower & Torque: 610 Horsepower / 510 ft. lbs. Torque

Cylinder Heads: BluePrint Engines LSX Style 6 Bolt Studded Aluminum Cylinder Heads

Compression Ratio: 9.5:1

Camshaft: Hydraulic Roller Cam - Hydraulic Roller Cam - .641 Intake / .641 Exhaust Lift - 236 Intake / 256 Exhaust Duration @0.050" 115.5 LSA - Three Bolt Cam

Piston: Mahle 2618 Custom Forged

Crankshaft: 8 Counterweight Forged Crank - 4.125" Stroke and 6.125" Rods

This engine Does NOT come with a Fuel Injection ECU and Wiring Harness.

Requires Race Fuel of 100+ Octane

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Financing available at checkout with Affirm

**BluePrint Motorsports engines are built for maximum performance and are intended for extreme duty race applications. If this engine is used in a street application our normal 30 month, 50,000-mile warranty applies, if used in sanctioned racing no warranty, expressed, or implied.

Overview:

BluePrint Motorsports introduces the ultimate 427ci LS Chevy-compatible long block, purpose-built for maximum boosted horsepower. Whether you’re chasing wins on the drag strip, sliding through drift circuits, tackling off-road trails, or carving up autocross courses, this engine delivers the perfect blend of power and reliability. At its foundation is a high-strength LSX-style cast-iron block, designed to handle extreme boost from nitrous, superchargers, or turbos. Topping it off are BluePrint Engines LS3 aluminum heads, paired with a BluePrint hydraulic roller cam for optimized airflow and performance across the powerband. Inside, a forged 8cwt crankshaft and forged H-beam rods provide rock-solid strength, while Mahle 2618 custom forged pistons ensure unmatched durability under pressure.

Description: 

  • Horsepower & Torque: 610 Horsepower / 510 ft. lbs. Torque
  • Compression Ratio: 9.5:1
  • BluePrint Engines LS3 Aluminum Heads
  • BluePrint Engines Hydraulic Roller Cam
  • BluePrint Engines Forged Crankshaft
  • Mahle 2618 Custom Forged Pistons

Block:

  • BluePrint Engines High Strength Cast Iron (LSX Style) Block 
  • Increased Deck Thickness and Strength Webbing
  • Utilizes OEM LS3 Front and Rear Covers
  • Improved Water Jacket Design
  • Extended Cylinder Skirt
  • 1-piece Rear Main Seal
  • Priority Main Oiling
  • 4.0695" Bore
  • 6-bolt studded mains
  • Billet Main Caps

Rotating Assembly:

  • Forged 8cwt Crankshaft
  • 4.125" Stroke
  • Forged H-Beam 6.125" Connecting Rods
  • Mahle Custom 2618 Forged Pistons
  • Internally Balanced Front and Rear

Cylinder Heads:

  • BluePrint Aluminum Cylinder Heads -PS8020
  • LSX Style 6 Bolt Studded Heads
  • 70cc Chamber
  • 2.165" Intake / 1.600" Exhaust Valves
  • 259cc Intake / 102cc Exhaust Runners

Cam Specs:

  • Hydraulic Roller
  • .641 intake / .641 Exhaust Lift
  • 236 Intake / 256 Exhaust Duration
  • @.050-115.5 Degree Lobe Separation

Also Includes:

  • This engine does NOT come with a Fuel Injection ECU and Wiring Harness
  • Harmonic Balancer
  • LS Swap Oil Pan
  • Valve Covers
  • Timing Cover

Notes:

  • BluePrint Motorsports engines are built for maximum performance and are intended for extreme duty applications. Because of the high-stress nature of their use, these engines are sold without any warranty, expressed, or implied.

WARNING: Cancer and Reproductive Harm
Bragging Rights Included.

EVERY BLUEPRINT ENGINE ACES THE DYNO TEST

We make sure we hit our target horsepower and proper torque with every crate engine. We use an advanced computerized balancer in our in-house dyno testing rooms to get our rotating assemblies within two grams, ensuring silky smooth power over the entire RPM range. That’s precisely why our engines sound and run better than our competitors.

All specs, zero speculation: A comprehensive, dyno-generated printout showing your critical engine specs will accompany your delivered engine — every time. No more guessing or wondering what your installed engine’s real-world peak horsepower and torque ratings actually are. Any doubters in the crowd? Simply flash ‘em your exact engine’s dyno results.

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