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.
Part Number: 88890534
Engine Type: Chevy Big-Block V-8
Displacement (cu in): 502
Bore x Stroke (in): 4.47 x 4.00
Block: Cast-iron with 4-bolt main caps
Crankshaft: Forged steel
Connecting Rods: Forged steel, shot peened
Pistons: Forged aluminum
Camshaft Type: Hydraulic roller
Camshaft Lift (in): .480 intake / .483 exhaust
Camshaft Duration (@.050 in): 204° intake / 209° exhaust
Cylinder Heads: Iron oval port; 118cc chambers
Valve Size (in): 2.07 intake / 1.73 exhaust
Compression Ratio: 8.75:1
Rocker Arms: Stamped steel
Rocker Arm Ratio: 1.7:1
Flexplate: 14"
Recommended Fuel: Regular pump
Ignition Timing: 34° Total at 4,000 rpm
Maximum Recommended rpm: 5,500
Balanced: External
• Requires the addition of carburetor, intake manifold, water pump, fuel pump, starter, distributor and ignition system (not included)
• Clutch linkage bosses are now drilled and tapped. When using cast-iron exhaust manifolds, lower head bolts may need to be replaced with bolts with shorter heads, for clearance
• 502 engines now have a mechanical fuel pump boss! NOTE: There is NO fuel pump lobe behind the boss.
• Comes with an externally balanced 14" automatic transmission flexplate. Use externally balanced flywheel P/N 14096987 and 11" clutch assembly for manual transmission applications
• Designed for pre-1976 street vehicles or any off-road vehicle
• Not intended for marine applications