Truck Conversion Kit CRATE ENGINES BIG-BLOCK Our HT502 Emission Legal (50 state) ... is designed for 1991-93 Chevrolet and GMC 10-, 20-, and 30-series trucks with ... wheel drive, originally equipped with a 454 TBI engine and 4L80E automatic ... -in replacement for any high-mileage 454. With more cubic inches, improved ... more torque than the factory 454 ever delivered. The HT502 engine comes ... assembled with an oil pan, timing set, valvetrain, valve covers, and ... , as well as the balancer, oil pan and timing chain set. Just add GMPP or your custom ...