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Top Street Performance

Chevy LS3 Assembled Aluminum Cylinder Head

Chevy LS3 Assembled Aluminum Cylinder Head

SKU: JM4620

$695.00
$695.00
Shipping calculated at checkout.

Low stock

Top Street Performance (TSP) is committed to providing high-quality performance parts while complying with emissions regulations. This product is designed for use on vehicles that comply with federal emissions regulations. It is the customer’s responsibility to verify that this part is legal for use in their state or local jurisdiction. Check with your local emissions authority before purchasing.

Product Details

Features

  • Fits GM LS Gen III/IV applications; verify cathedral or rectangular port compatibility before ordering
  • 260cc intake runners, 64 cc chambers, 2.165 in./1.590 in. valves for improved airflow and power potential
  • Assembled with performance valves, springs, retainers, locks and seals for easier installation
  • Lightweight aluminum construction improves heat dissipation versus factory iron castings

Description

Upgrade your GM LS with assembled aluminum cylinder heads engineered to provide reliable airflow and combustion efficiency for street and performance builds. Featuring 260cc intake runners, 64 cc combustion chambers, 2.165 in. intake / 1.590 in. exhaust valves, these heads are built for street, strip, and performance engine builds that need better breathing than stock castings.

Improved Airflow & Power Potential
Optimized runner and chamber design helps move more air through the engine, improving throttle response, torque, and top-end horsepower potential across the RPM range.

Assembled Valve Train Setup
Delivered assembled with matched valves, springs, retainers, locks, and seals where specified, helping simplify installation for performance camshaft applications.

Aluminum Construction
Lightweight aluminum construction reduces weight compared to factory iron heads while improving heat dissipation for more consistent performance under demanding conditions.

Built for Street & Performance Builds
Ideal for performance rebuilds, restorations, and upgraded engine combinations. Always verify piston-to-valve clearance, camshaft compatibility, intake manifold fit, and header clearance before final installation.

Specs

Assembled Yes
CNC Ported No
Combustion Chamber Style Heart
Combustion Chamber Volume 64 cc
Deck Height Standard
Deck Thickness Standard
Exhaust Crossover No
Exhaust Port Location Standard
Exhaust Port Shape D-port
Exhaust Valve Diameter 1.590 in.
Exhaust Valve Material Stainless Steel
Finish Natural
Grade Type Performance
Guide Plate Material Bronze
Intake Port Location Standard
Intake Port Shape Cathedral
Intake Runner Volume 260cc
Intake Valve Diameter 2.165 in.
Intake Valve Material Stainless Steel
Material Aluminum
Quantity Sold Individually
Valve Guide Material Bronze
Valve Seat Material steel
Valve Spring Maximum Lift 0.660 in.
Valve Spring Retainer Material Chromoly Steel
Valve Springs Included No
Valves Included Yes

Engine Fitment

COMPATIBLE WITH
GM LS SERIES V8 ENGINES - RECTANGULAR PORT
• 6.0L / 364 in³ (L76, L77, L98)
• 6.2L / 376 in³ (LS3, L92, L99, L9H)
• 7.0L / 427 in³ (LS7 requires application-specific verification)

COMMON VEHICLE APPLICATIONS
Chevrolet Corvette (LS3 equipped)
Chevrolet Camaro (LS3 / L99 equipped)
Chevrolet SS / Pontiac G8 (LS3 / L76 equipped)
Cadillac CTS-V applications using compatible LS architecture
GM trucks and swaps using rectangular-port LS cylinder heads

NOTES

Designed for rectangular-port LS intake manifold applications.

Verify intake manifold, rocker arm, valve cover, head gasket bore, and head bolt/stud compatibility before installation.

Cylinder head sold individually (purchase quantity of 2 required for complete engine).

Not compatible with cathedral-port LS intake manifolds, Gen V LT direct-injection engines, Gen I SBC, or Big Block Chevy engines.

Q&A

Emissions Notice

This product is legal for off road use and non pollution controlled vehicles (1965 & older); however, it has not been tested or approved by the California Air Resources Board (CARB) for highway vehicles in the state of California. By purchasing this product, buyer agrees it will not be used on pollution controlled vehicles in California, or in a state with similar emissions regulations.