Hawks Motorsports offers the BluePrint Engines G4547090 GM Big Block Compatible 454 C.I. Long Block, a 50-state legal OEM-spec replacement engine designed for select 1970-1990 GM Big Block Chevrolet applications. Built to factory specifications while utilizing tighter machining tolerances, premium internal components, and precision balancing, this engine delivers the reliability and drivability of an original replacement engine while meeting emissions requirements for use in all 50 states.

The G4547090 is assembled using a BluePrint high-strength cast iron 454 block featuring a 4.250-inch bore, 4.000-inch stroke cast crankshaft, OEM-style 6.135-inch connecting rods with 150,000 PSI bolts, and OEM-spec hypereutectic pistons. Cast iron cylinder heads and an OEM-spec hydraulic flat tappet camshaft provide factory-equivalent performance while maintaining compatibility with the original induction, ignition, exhaust, and engine management systems. Horsepower and torque remain at OEM specifications, making this engine ideal for restoration projects and emissions-compliant replacements.

The long block arrives assembled with the timing cover, harmonic balancer, valve covers, and dipstick installed. Customers reuse their original intake manifold, fuel system, exhaust manifolds, distributor or ignition system, accessories, and electronics where applicable. This engine is dyno-tested and backed by BluePrint Engines' 30-Month / 50,000-Mile Warranty.

Key Features:

• SKU: G4547090
• GM Big Block Compatible 454 C.I. Long Block
• 50-State Legal OEM replacement engine
• Designed for select 1970-1990 GM applications
• OEM horsepower and torque output
• BluePrint high-strength cast iron block
• Cast iron cylinder heads
• 4-bolt main block
• 4.250" bore
• 4.000" stroke
• Cast crankshaft
• OEM-style 6.135" connecting rods
• 150,000 PSI rod bolts
• OEM-spec hypereutectic pistons
• Flat tappet camshaft
• Camshaft Specs:
  • .409" Intake Lift
  • .442" Exhaust Lift
  • 193° Intake Duration @ .050"
  • 203° Exhaust Duration @ .050"
• 1-piece rear main seal
• Mechanical fuel pump provision
• External front balance / Internal rear balance
• Harmonic balancer installed
• Timing cover installed
• Valve covers installed
• Dipstick installed
• Manufactured and machined in the USA
• 30-Month / 50,000-Mile Warranty

Fitment Applications:

Designed as a factory replacement for select 1970-1990 GM Big Block Chevrolet vehicles, including qualifying:

• Chevrolet C/K Pickup
• Chevrolet Suburban
• Chevrolet Blazer
• GMC C/K Pickup
• GMC Jimmy
• GMC Suburban
• Chevrolet P-Series chassis
• Additional GM vehicles originally equipped with compatible 454 engines

Refer to BluePrint's official application guide before ordering to verify compatibility with your specific year and vehicle.

Installation Notes:

• Long block assembly only.
• Reuse OEM intake manifold.
• Reuse OEM exhaust manifolds.
• Reuse OEM fuel system.
• Reuse OEM ECU or ignition components where applicable.
• Water pump not included.
• Distributor not included.
• Accessory drive not included.
• This engine utilizes a 1-piece rear main seal. Vehicles originally equipped with a 2-piece rear main seal will require the appropriate flywheel or flexplate conversion.
• Recommended BluePrint harmonic balancer: BPP454E
• Recommended weighted Gen V 42.5 oz. flywheel/flexplate.
• Ignition timing is controlled by OEM specifications or factory ECU.