Chevrolet Performance’s 525 RLB is based on the LS engine family and is like the
6.2L CT525 but sold as a sealed long block for universal racing sanctioning bodies.

The high-revving 525 RLB crate engine is assembled with strong forged pistons and
heavy-duty connecting rod bolts designed to support its performance capability
and enhance its durability. With its deep-breathing LS3 rectangular-port cylinder
heads, it is a combination rated at 533 horsepower at 6,600 rpm and a strong 477
lb.-ft. of torque at 5,200 rpm, when used with a 4-barrel carburetor and intake
manifold, per Chevrolet Performance testing.

The engine assembly comes with coil-on-plug ignition and an SFI-certified
balancer, along with a 6-quart racing oil pan and more. All that’s needed to
complete the assembly is an induction and ignition system — and all those
components are also available from Chevrolet Performance.

INSTALLATION NOTES

Requires addition of induction and ignition control system, starter, fuel system,
exhaust system and front accessory drive system
The 6-quart racing oil pan is designed to clear most GM rear-steer chassis with stock engine location

The long block is designed for universal racing sanctioning bodies. It is not
intended for street use

The 525RLB does not included water pump, intake manifold or factory exhaust
manifolds

Chevrolet Performance Racing Long Block engines include factory-installed
anti-tampering seals

TECH SPECS

Part Number: 19435005
Engine Type: LS-Series Gen IV Small-Block V-8
Displacement (cu in): 376 (6.2L)
Bore x Stroke (in): 4.065 x 3.62 (103.25 x 92mm)

Block (P/N 12729604): Cast aluminum with 6-bolt, cross-bolted main caps

Crankshaft (P/N 12736809): Nodular iron

Connecting Rods (P/N 12649190): Powder metal with ARP bolts

Pistons (P/N 19418214): Forged aluminum

Camshaft Type (P/N 88958770): Hydraulic roller

Valve Lift (in): .525 intake / .525 exhaust

Camshaft Duration (@.050 in): 226° intake / 236° exhaust

Cylinder Heads (P/N 12675871): LS3 rectangular port; aluminum as-cast with 68cc chambers

Valve Size (in): 2.165 intake / 1.590 exhaust

Compression Ratio: 10.7:1 Nominal

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 Recommended rpm: 6,700

Reluctor Wheel: 58x

Balanced: Internal

*If equipped with 4 Barrel Carbureted Induction System.