421 Intimidator SBC Forged Short Block
The Reid's Speed Shop 421 Intimidator represents the pinnacle of our Small Block Chevrolet stroker short block lineup. Combining substantial displacement with a heavy-duty Dart SHP aftermarket engine block and a premium fully forged rotating assembly, the Intimidator provides an exceptional foundation for serious street performance and demanding high-horsepower applications.
At its foundation is a Dart SHP engine block featuring billet steel splayed four-bolt main caps, 350-size main journals, and a one-piece rear main seal. An Eagle 4340 forged steel crankshaft with an increased 3.875" stroke, forged 6.000" H-beam connecting rods with ARP hardware, and Wiseco forged pistons provide a robust rotating assembly designed for strength, durability, and exceptional performance potential.
The increased stroke and displacement offer outstanding potential for low-end torque, substantial midrange power, and impressive horsepower when paired with a properly matched top-end combination.
Every short block receives professional machine work, careful component preparation, precision measurements, and final assembly using the same standards applied to our complete engine builds. Each engine block is painted in your choice of color, with low-gloss black included as standard.
Standard Forged Short Block
Starting at $6,399
Dart SHP Heavy-Duty Aftermarket Small Block Chevrolet Block
Billet Steel Splayed Four-Bolt Main Caps
350-Size Main Journals
One-Piece Rear Main Seal
Eagle 4340 Forged Steel Crankshaft, 3.875" Stroke
Forged 6.000" H-Beam Connecting Rods
ARP Connecting Rod Hardware
Wiseco Forged Pistons, 4.155" Bore
King XP Coated Main and Rod Bearings
Premium Plasma Moly Piston Rings
Installed and Properly Clocked Coated Camshaft Bearings
Brass Expansion Plug Kit
Complete Professional Machine Work and Block Preparation
Precision Measurements and Rotating Assembly Installation
Engine Block Painted in Your Choice of Color (Low-Gloss Black Standard)
This configuration provides a professionally assembled, fully forged short block ready to serve as the foundation for your selected valvetrain, cylinder heads, induction system, and remaining engine components.
Available Package Upgrades
Hydraulic Roller Camshaft Package
+$1,300
Includes everything in the Standard Forged Short Block, plus:
Custom-Selected Hydraulic Roller Camshaft, Professionally Installed and Degreed
Johnson Hylift Hydraulic Roller Lifters
New Hydraulic Roller Lifter Retainer Kit
Lifter Spider Tray and Dogbone Retainers
9-Way Adjustable Billet Double Roller Timing Set with Torrington Bearing
ARP Camshaft Hardware
Three camshaft stages are available to accommodate different driving characteristics and performance goals, ranging from responsive street performance to more aggressive, higher-output combinations.
Customers seeking a specific camshaft profile or a specialized application are welcome to contact Reid's Speed Shop for a custom recommendation.
Hydraulic Roller Camshaft + Sealed Short Block Package
+$1,900 over the Standard Short Block
Includes everything in the Hydraulic Roller Camshaft Package, plus:
Melling M55 Engine Oil Pump
Properly Matched Oil Pump Pickup, Installed at the Appropriate Depth
ARP Oil Pump Mounting Hardware
Moroso Stroker-Clearanced Oil Pan
One-Piece Oil Pan Gasket
ARP Oil Pan Hardware
Polished Timing Cover
Timing Cover Gasket and Front Crankshaft Seal
ARP Timing Cover Hardware
This configuration provides a more complete, professionally assembled and sealed short block with the camshaft, timing components, oiling system, timing cover, and oil pan installed.
It is an excellent choice for customers looking to simplify the completion of their engine while ensuring these critical components are properly selected, matched, and assembled.
Built Around Your Goals
The 421 Intimidator is designed for enthusiasts looking to maximize the performance potential of the traditional Small Block Chevrolet platform. Its substantial displacement and premium forged rotating assembly provide an excellent foundation for building a powerful street engine or a more aggressive performance combination.
Whether you're looking for exceptional low-end torque, strong acceleration throughout the RPM range, or a higher-output combination designed for spirited driving, the Intimidator can be tailored to complement your intended application.
Customers can select their own compatible top-end components or pair their short block with one of our performance top-end packages for a more complete, coordinated engine combination.
Every 421 Intimidator is professionally prepared and assembled by Reid's Speed Shop, with an emphasis on precision, component compatibility, and the same attention to detail found throughout our complete engine builds.
Cylinder heads, intake manifold, and other top-end components are sold separately. Final compression ratio depends on cylinder head combustion chamber volume, head gasket specifications, piston configuration, and assembled dimensions. Additional components are required to complete the engine.
The Reid's Speed Shop 421 Intimidator represents the pinnacle of our Small Block Chevrolet stroker short block lineup. Combining substantial displacement with a heavy-duty Dart SHP aftermarket engine block and a premium fully forged rotating assembly, the Intimidator provides an exceptional foundation for serious street performance and demanding high-horsepower applications.
At its foundation is a Dart SHP engine block featuring billet steel splayed four-bolt main caps, 350-size main journals, and a one-piece rear main seal. An Eagle 4340 forged steel crankshaft with an increased 3.875" stroke, forged 6.000" H-beam connecting rods with ARP hardware, and Wiseco forged pistons provide a robust rotating assembly designed for strength, durability, and exceptional performance potential.
The increased stroke and displacement offer outstanding potential for low-end torque, substantial midrange power, and impressive horsepower when paired with a properly matched top-end combination.
Every short block receives professional machine work, careful component preparation, precision measurements, and final assembly using the same standards applied to our complete engine builds. Each engine block is painted in your choice of color, with low-gloss black included as standard.
Standard Forged Short Block
Starting at $6,399
Dart SHP Heavy-Duty Aftermarket Small Block Chevrolet Block
Billet Steel Splayed Four-Bolt Main Caps
350-Size Main Journals
One-Piece Rear Main Seal
Eagle 4340 Forged Steel Crankshaft, 3.875" Stroke
Forged 6.000" H-Beam Connecting Rods
ARP Connecting Rod Hardware
Wiseco Forged Pistons, 4.155" Bore
King XP Coated Main and Rod Bearings
Premium Plasma Moly Piston Rings
Installed and Properly Clocked Coated Camshaft Bearings
Brass Expansion Plug Kit
Complete Professional Machine Work and Block Preparation
Precision Measurements and Rotating Assembly Installation
Engine Block Painted in Your Choice of Color (Low-Gloss Black Standard)
This configuration provides a professionally assembled, fully forged short block ready to serve as the foundation for your selected valvetrain, cylinder heads, induction system, and remaining engine components.
Available Package Upgrades
Hydraulic Roller Camshaft Package
+$1,300
Includes everything in the Standard Forged Short Block, plus:
Custom-Selected Hydraulic Roller Camshaft, Professionally Installed and Degreed
Johnson Hylift Hydraulic Roller Lifters
New Hydraulic Roller Lifter Retainer Kit
Lifter Spider Tray and Dogbone Retainers
9-Way Adjustable Billet Double Roller Timing Set with Torrington Bearing
ARP Camshaft Hardware
Three camshaft stages are available to accommodate different driving characteristics and performance goals, ranging from responsive street performance to more aggressive, higher-output combinations.
Customers seeking a specific camshaft profile or a specialized application are welcome to contact Reid's Speed Shop for a custom recommendation.
Hydraulic Roller Camshaft + Sealed Short Block Package
+$1,900 over the Standard Short Block
Includes everything in the Hydraulic Roller Camshaft Package, plus:
Melling M55 Engine Oil Pump
Properly Matched Oil Pump Pickup, Installed at the Appropriate Depth
ARP Oil Pump Mounting Hardware
Moroso Stroker-Clearanced Oil Pan
One-Piece Oil Pan Gasket
ARP Oil Pan Hardware
Polished Timing Cover
Timing Cover Gasket and Front Crankshaft Seal
ARP Timing Cover Hardware
This configuration provides a more complete, professionally assembled and sealed short block with the camshaft, timing components, oiling system, timing cover, and oil pan installed.
It is an excellent choice for customers looking to simplify the completion of their engine while ensuring these critical components are properly selected, matched, and assembled.
Built Around Your Goals
The 421 Intimidator is designed for enthusiasts looking to maximize the performance potential of the traditional Small Block Chevrolet platform. Its substantial displacement and premium forged rotating assembly provide an excellent foundation for building a powerful street engine or a more aggressive performance combination.
Whether you're looking for exceptional low-end torque, strong acceleration throughout the RPM range, or a higher-output combination designed for spirited driving, the Intimidator can be tailored to complement your intended application.
Customers can select their own compatible top-end components or pair their short block with one of our performance top-end packages for a more complete, coordinated engine combination.
Every 421 Intimidator is professionally prepared and assembled by Reid's Speed Shop, with an emphasis on precision, component compatibility, and the same attention to detail found throughout our complete engine builds.
Cylinder heads, intake manifold, and other top-end components are sold separately. Final compression ratio depends on cylinder head combustion chamber volume, head gasket specifications, piston configuration, and assembled dimensions. Additional components are required to complete the engine.