You are currently viewing Chevrolet.com (United States). Close this window to stay here or choose another country to see vehicles and services specific to your location.

LS9 LONG-BLOCK

QUALITY PARTS.
HIGH-CALIBER BUILD.

Offer Valid 1/1/24 to 12/31/24

$250 rebate* on the purchase of a Chevrolet Performance Transmission within 180 days of the purchase of any Chevrolet Performance Crate Engine**. Rebate amount dependent on the package purchased.

QUALITY PARTS.
HIGH-CALIBER BUILD.

Offer Valid 1/1/24 to 12/31/24

$250 rebate* on the purchase of a Chevrolet Performance Transmission within 180 days of the purchase of any Chevrolet Performance Crate Engine**. Rebate amount dependent on the package purchased.

COMPLETE YOUR PERFECT BUILD

OFFER VALID 1/1/23 TO 12/31/23.

$250 rebate on the purchase of a Chevrolet Performance Transmission within 180 days of the purchase of any Chevrolet Performance Crate Engine

PARTS INTENDED FOR COMPETITION USE ONLY.
Click for more details.

PARTS INTENDED FOR COMPETITION USE ONLY.
Click for more details.

PROPOSITION 65 WARNING.
Click for more details.

PROPOSITION 65 WARNING.
Click for more details.

A factory foundation for boost

As the foundation for the supercharged engine that powered the 2009-13 Corvette ZR1, our LS9 is a long-block built for boost – delivered without the supercharger or front-end accessory drive system, allowing the builder to finish the engine with the power adder of his or her choice. It is rated for 12 lbs. of boost.

PART NO. 12624262

Chevrolet Performance Animated speedometer

638 HP @6500 RPM

Chevrolet Performance Animated gears

604 LB-FT @ 3800 RPM

Building boost

The assembly includes a forged rotating assembly (including lightweight titanium connecting rods), rotocast aluminum cylinder heads with titanium intake valves and stainless hollow exhaust valves, multiple engine sensors and six ignition coils. It also includes a dry-sump oil pan, which requires the builder to add an external oil tank.

LS9 Long-Block Tech Specs

  • Engine Type: LS-Series Gen-IV Small-Block V-8
  • Displacement (cu. in.): 376 (6.2L)
  • Bore x Stroke (in.): 4.065 x 3.622 (103.25 x 92 mm)
  • Block: Cast-aluminum with six-bolt, cross-bolted main caps
  • Crankshaft (P/N 12641693): Forged steel with nine-bolt flange
  • Connecting Rods (P/N 12624231): Forged titanium
  • Pistions (P/N 19180414): Forged alumium
  • Camshaft Type (P/N 12638427): Hydraulic roller
  • Valve Lift (in.): .562 intake / .558 exhaust
  • Cylinder Heads (P/N 12621774): Aluminum L92-style ports; “as cast” with 68-cc chambers
  • Valve Size (in.): 2.160 titanium intake / 1.590; hollow, sodium-filled exhaust
  • Compression Ratio: 9.1:1
  • Rocker Arms (P/N 12696105 int.): Investment-cast, roller trunnion
  • Rocker Arms (P/N 12681275 exh.): Investment-cast, roller trunnion
  • Rocker Arm Ratio: 1.7:1
  • Recommended Fuel: Premium pump
  • Maximum recommend rpm: 6600
  • Reluctor Wheel: 58X
  • Balanced: Internal

LS9 CNC-Ported Head Assembly (intake)

LS9 CNC-Ported Cylinder Head Assembly (exhaust)

LS9 CNC-Ported Cylinder Head Assembly (combustion chamber)

LS9 CNC-Ported Head Assembly (intake)

LS9 CNC-Ported Cylinder Head Assembly (exhaust)

LS9 CNC-Ported Cylinder Head Assembly (combustion chamber)

All-New LS9 CNC-Ported Cylinder Head Assembly 

PART NO. 19433498

  • Fits all LS engines with 4.000” bore or larger
  • 276cc intake ports
  • 68.5cc chamber volume
  • 2.165” hollow stem intake and 1.590” solid stem exhaust valves
  • .550” max valve lift
  • L92-style intake ports and D-shaped exhaust ports

Installation Guides

Find everything from vital data about your engine’s capabilities to how to install it into your build.

Mobil 1 is now The Official Motor Oil of Chevrolet Performance.

VISIT OUR BRANDS FOR YOUR OE NEEDS

Unless specifically noted to the contrary herein, vehicles equipped with Chevrolet Performance parts that are emissions-related may not meet U.S., Canadian, and state and provincial laws and regulations relating to motor-vehicle emissions. These parts are designed and intended for use in vehicles operated exclusively for competition: in racing or organized competition on courses separate from public streets or highways. Visit www.chevroletperformance.com/emissions for more details.