LS3 Crate Engine – Chevrolet Performance LS376/525 Long Block Engine


  • 525 hp @ 6,200 rpm/486 lb.-ft. @ 5,200 rpm


REBATE AVAILABLE: $350 Prepaid VISA Gift Card From Chevrolet Performance. See 'Rebate' tab below for details.

Shipping is free, but there is a delivery fee for residential addresses.

LS376/525 Long Block Crate Engine

Chevrolet Performance’s naturally aspirated 6.2 liter engine features an aggressive ASA camshaft developed for the high-rpm world of circle-track racing. Installed in the LS3 6.2L engine, it comes alive with 525 uncompromising horsepower. That makes it the most powerful naturally aspirated 6.2L street engine in our portfolio!

The ASA camshaft is a hydraulic roller with .525-inch lift on both sides, along with 226 degrees duration on the intake side and 236 degrees on the exhaust side. Coupled with a tight, 110-degree lobe separation angle, it helps the engine deliver excellent throttle response and breathe exceptionally well at high rpm. And for durability, we complement the cam with higher-rate valve springs.

What’s Included

  • Fully GM assembled long block
  • Oil pump, pick-up and Camaro oil pan
  • Harmonic Balancer
  • Front timing cover
  • Oil Filter

Important Notes

  • Assembly does not include any electronics, intake manifold, fuel system, or ignition.
  • Includes Chevy F-Body wet sump oil pan
  • Intended for pre-1976 street vehicles or any off-road vehicle
  • Not intended for marine applications
  • Coolant Crossover & Oil Dipstick and Tube NOT INCLUDED
  • Replaces 19432557,19420386, and 19434648
Weight 486 lbs

Manufacturer Part Number




LS376/525 Tech Specs

  • Engine Type: LS-Series Gen IV Small-Block V-8
  • Displacement (cu in): 376 cu in (6.2L)
  • Bore x Stroke (in): 4.065 x 3.622 (103.25 x 92mm)
  • Block: Cast aluminum with 6-bolt, cross-bolted main caps (P/N 12623967)
  • Crankshaft: Nodular iron (P/N 12597569)
  • Connecting Rods: Powdered metal (P/N 12607475)
  • Pistons: Hypereutectic aluminum (P/N 19207287)
  • Camshaft Type: Hydraulic roller (P/N 88958770)
  • Valve Lift (in): 0.525 intake / 0.525 exhaust
  • Camshaft Duration (@0.050 in): 226° intake / 236° exhaust
  • Cylinder Heads: Aluminum L92-style port; as cast with 68cc chambers (P/N 12629063)
  • Valve Size (in): 2.165 intake / 1.590 exhaust
  • Compression ratio: 10.7:1
  • Rocker Arms: Investment cast, roll trunnion (P/N 1266999)
  • Rocker Arms: Investment cast, roll trunnion (P/N 12669993)
  • Rocker Arm Ratio: 1.7:1
  • Recommended Fuel: Premium pump
  • Maximum Recommended RPM: 6,600
  • Reluctor Wheel: 58x
  • Balanced: Internal

Chevrolet Performance Crate Engines carry a 24 Month or 50,000 mile warranty (whichever comes first) when installed by a qualified independent service center. Chevrolet Performance Crate Engines also come with a 30 day start up warranty (parts only).

There are some additional limitations on the warranty – please see the official GM warranty documentation for more information.

$350 Rebate on LS Engine and Long Blocks through July 31, 2024. Click here for details.


There are no reviews yet.

Be the first to review “LS3 Crate Engine – Chevrolet Performance LS376/525 Long Block Engine”
Prop65WARNING: These auto parts can expose you to chemicals including phthalates and lead. Installing or using these parts can expose you to other parts containing these chemicals and to engine exhaust, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to

You may also like…

  • Sale!

    LS3 Intake Manifold

    Add to cart
  • Holley 300-129BK LS3 Dual Plane Carb Intake & MSD 60143 Ignition Box

    Add to cart
  • Sale!

    Allstar Ignition Coil Mounting Brackets

    Add to cart
  • Sale!

    MSD 60143 Black Ignition Control, LS

    Add to cart