HT502
An affordable, high-performance alternative to rebuilding
If you’re thinking about repowering your trusty Big-Block-powered truck, don’t bother with a rebuild or a reconditioned used engine. Chevrolet Performance’s HT502 crate engine is an affordable alternative with more power and greater durability.
The HT502 is rated at 406 horsepower and a whopping 541 lb-ft of trailer-tugging torque. That’s more than the factory ever offered and more than you’ll get with a stock-type rebuild. It is uniquely suited to pre-1978 trucks, but is adaptable to a variety of applications.
We build the HT502 with a forged crankshaft, rods, and pistons for maximum strength, and they’re installed in a new version of the Big-Block cylinder block. It is updated for greater strength and performance capability. A conservative 8.75:1 compression ratio ensures pump-gas performance at all altitudes and engine loads.
Our assembly comes with heads and a balancer installed. An induction system, ignition, starter, water pump, and other accessories are required to finish the engine. All necessary components are available from Chevrolet Performance.
Horsepower
406 HP
Torque
541 LB-FT
Tech Specs
Engine Type: Chevy Big-Block V-8
Displacement (cu. in.): 502
Bore x Stroke (in.): 4.47 x 4.00
Block (P/N 19170540): Cast-iron with four-bolt main caps
Crankshaft (P/N 10183723): Forged steel
Connecting Rods (P/N 19170198): Forged steel, shot peened
Pistons (P/N 12533507): Forged aluminum
Camshaft Type (P/N 12552296): Hydraulic roller
Camshaft Lift (in.): .480 intake / .483 exhaust
Camshaft Duration (@.050 in.): 204° intake / 209° exhaust
Cylinder Heads (P/N 12562917): Iron oval port; 118-cc chambers
Balanced: External
Valve Size (in.): 2.070 intake / 1.730 exhaust
Compression Ratio: 8.75:1
Rocker Arms (P/N 12523976): Stamped steel
Rocker Arm Ratio: 1.7:1
Flexplate (P/N 10185034): 14"
Recommended Fuel: 92 octane
Ignition Timing: Base 4° BTDC, 26° Total
Maximum Recommended rpm: 5500