441 LS Short Block - Specs, Applications, and Big Power Builds

What is a 441 LS Short Block?

The 441 LS short block is a popular performance engine component used in many GM vehicles. LS refers to GM's Gen III/IV small block engine family that debuted in 1997. The 441 designation indicates a 4.41 inch bore size combined with a 3.622 inch stroke crankshaft.

This oversquare cylinder configuration results in a total displacement of 6.0 liters (364 cubic inches). The 441 LS short block is the foundation for high performance 6.0L LS engine builds used in Chevrolet, GMC, Cadillac, and Pontiac vehicles.

LS Engine Background

GM introduced the LS family in 1997 with the all-new C5 Corvette. The first LS1 engines featured an all-aluminum construction that was much lighter than the traditional small block V8 cast iron design.

This new lightweight design paid huge dividends for performance and fuel efficiency. Additional improvements included coil-near-plug ignition, improved cylinder head airflow, and advanced electronic engine controls.

The LS1 established an excellent reputation for reliability and performance. Its success led GM to expand the LS family to include various displacements used across their entire vehicle lineup. This ranged from 5.3L truck engines to supercharged 6.2L models for the Corvette ZR1.

441 LS Short Block Specs

The 441 LS short block combines the following components:

• 4.41 inch alloy cylinder block bore
• 3.622 inch forged steel crankshaft stroke
• 6.0L (364 cubic inch) total displacement
• Aluminum cylinder heads (rectangular or cathedral port)
• High volume oil pump
• Capped cam bore in block (for cam-in-block engines)

This robust short block is capable of handling very high horsepower build levels. The strong cylinder block casting and forged crankshaft can reliably withstand boost levels exceeding 30 psi.

441 LS Block Construction

The 441 LS block features GM's rugged Generation IV architecture first introduced on the 6.0L LQ9 engine. It utilizes six-bolt, cross-bolted main caps secured to deep skirt block walls with premium grade hardware.

Additional key block features include:

• Siamese cylinder bores
• 9.24" deck height
• Priority main oiling system
• Bay-to-bay breathing cylinder cooling

This incredibly sturdy bottom end is capable of supporting over 800 horsepower in stock form. Modifications can strengthen it to withstand four digit output levels.

Forged 4340 Steel Crankshaft

The 3.622" stroke rotating assembly consists of a forged 4340 steel crank mated with forged I-beam connecting rods. This is an extremely durable component set designed for high RPM operation.

Key features include:

• 58X reluctor wheel
• Fillet rolled bearing journals
• Chamfered oil holes
• Nitride hardened surface
• Internal balancing

This forged bottom end is capable of handling tremendous boost levels. With the right supporting modifications, the 441 LS short block can produce over 1200 horsepower.

High Volume Oil Pump

The oiling system upgrades start with a high capacity, high pressure oil pump. This pumps 60-80 psi at idle and over 100 psi at higher RPMs.

Benefits include:

• Maximizes oil flow to vital areas
• Prevents bearing and valve train wear
• Increases reliability under hard use
• Handles high spring pressures in aggressive cam profiles

This pump ensures robust lubrication for the entire engine, even at redline RPM levels.

Rectangular vs Cathedral Port Heads

441 LS short blocks are typically sold with cathedral port or rectangular port cylinder heads. Both deliver great performance, but have slightly different attributes.

Cathedral port heads feature a high flow, high velocity intake port design. Benefits include:

• Broad powerband
• Excellent low-end torque
• Great for truck/SUV applications
• Compatible with stock components

Meanwhile, rectangular port heads utilize a higher flowing, race-inspired straight shot intake port. Advantages include:

• Optimized for peak high RPM power
• Higher lift cam compatibility
• Increased tuning potential
• Ideal for dedicated performance builds

Both types yield great performance and 500+ hp capability when matched with supporting mods.

Typical 441 LS Short Block Applications

Some popular vehicles and engine swaps that utilize 441 LS power include:

• C6 Corvette LS2/LS3
• Camaro/Firebird LS1/LS2
• GTO LS1/LS2
• Trailblazer/Envoy LQ9
• SSR LS2
• Chevy S10/Colorado LS Swap
• Jeep TJ/LJ LS Swap
• Nissan 240SX LS Swap
• Miata LS Swap

The 441 LS short block makes an excellent high performance foundation for GM muscle cars, trucks, SUVs, and popular swap applications.

Building a High Performance 441 LS Short Block

The 441 LS engine readily supports 500+ horsepower with simple bolt-on modifications. Further upgrading the short block unlocks 800 to 1200+ hp potential.

Here are some popular upgrades for max performance:

Cylinder Block

• Bore & hone cylinders
• Machine for stroker/larger crank
• Cylinder sleeve installation
• Deck block for increased compression
• Upgrade cylinder head studs
• O-ring block for improved sealing

Crankshaft & Rods

• Increase stroke with 4340 steel crank
• Upgrade to H-beam or billet rods
• Balance rotating assembly
• Upgrade rod bolts

Pistons & Rings

• Forged aluminum pistons
• Low tension piston rings
• Upgrade wrist pins
• Modify compression height

Oiling System

• High volume oil pan
• Improved oil pump pickup
• Remote oil filter adapter
• accusump oiling assist

With meticulous machine work, optimized parts matching, and professional assembly, you can build an insanely powerful 441 LS short block for your high performance application.

441 LS Short Block: Final Thoughts

In summary, the 441 LS short block is a serious high performance foundation ready for big power builds. The stout Gen IV block combined with a forged bottom end makes an extremely durable package.

With upgraded internals like pistons, rods, and crankshaft, the 441 can easily support 1200+ horsepower. This makes it the perfect choice for boosted engines, racing applications, or an all-out street/strip build.

The LS platform offers phenomenal bang-for-the-buck power in a compact, lightweight, aluminum V8 design. For hardcore enthusiasts, the 441 short block is the ultimate base for your high horsepower dreams.

FAQs

What is the stock bore and stroke of a 441 LS block?

The 441 LS has a bore of 4.41 inches and a stroke of 3.622 inches from the factory.

What vehicles came equipped with 441 LS engines from GM?

The 441 LS was used in high performance models like the C6 Corvette Z06, Trailblazer SS, and SSR.

How much horsepower can a 441 LS produce with basic bolt-ons?

With just headers, cam, and tune, a 441 LS can reliably achieve 500+ horsepower.

What are the differences between cathedral port and rectangular port heads?

Cathedral ports offer better low-end torque while rectangular ports optimize top end power.

What upgrades are needed to reach 1000 hp with a 441 LS?

Getting to 1000 hp requires a built bottom end, upgraded heads, aggressive cam, ported intake, and large turbo or supercharger.