ATK HP103T Chrysler 5.7L Hemi 400 HP Truck Long Block Crate Engine

Description

Need dependable Ram truck towing power? Select the ATK HP103T Chrysler Crate Engine 5.7L Hemi Truck package. Engineered specifically for Dodge Ram 1500, 2500, and commercial fleet applications, this 5.7-liter Gen III Hemi V8 outputs 400 brake horsepower at 5,600 RPM. Built with truck-calibrated valvetrain components and high-flow aluminum cylinder heads, it provides exceptional low-RPM hauling stamina.

Technicians inspect seasoned Chrysler Gen III cast iron truck blocks, align-honing main journals and squaring block decks. A nodular iron crankshaft spins with internal neutral balance weighting inside a one-piece rear main seal. Forged powder metal connecting rods attach to 3.917-inch hypereutectic pistons across a 3.578-inch stroke. A 9.6:1 compression ratio pairs with dual-plug aluminum cylinder heads. Oil capacity requires 7.0 quarts in truck sumps. Bare long block weight totals 432 lbs.

Key Features of ATK HP103T

Truck owners and commercial fleet managers buy ATK HP103T crate engine units to replace exhausted factory truck engines with zero downtime. The long block bolts flush into Dodge Ram truck engine bays using factory subframe pads.

• Truck-specific camshaft profile optimizes low-RPM pulling torque and continuous hauling capacity.
• Dual-plug aluminum cylinder heads improve combustion flame travel under heavy trailer loads.
• Cross-bolted main bearing caps anchor the rotating group against structural bottom-end deflection.
• 345 cubic inch displacement provides modern Hemi muscle with manageable fuel consumption.
• OE hydraulic roller lifters reduce internal friction while extending valvetrain operating life.
• High-tensile cylinder head bolts maintain combustion seal under continuous wide-open throttle climbs.
• Internal neutral balance specification eliminates torsional vibrations through the transmission input shaft.
• Blueprinted ATK HP103T tolerances maintain correct hydrodynamic bearing oil clearance under load.

Dynamic Hemi Truck Dyno Output

Operating across a practical 2,000 to 5,800 RPM power band, this truck-spec Gen III Hemi generates 400 brake horsepower and 410 lb-ft torque on 89-octane pump gasoline. The OE hydraulic roller camshaft specifies 204 degrees intake duration at 0.050-inch lift with 0.500-inch valve lift. Manifold vacuum measures 17 in-Hg at a 650 RPM curb idle. Hot engine oil pressure runs between 45 to 65 PSI, keeping main bearings and overhead valvetrain parts lubricated during extended trailer towing pulls.

Engine Bay Subframe Fitment Clearances

This truck-application Hemi engine utilizes standard modern Chrysler truck transmission bolt patterns, bolting straight to 545RFE, 65RFE, and 8HP70 automatic transmissions. Internal neutral balancing requires zero-balance flexplates. Factory engine mount brackets align with stock Dodge Ram front subframe cradles. The front timing cover area accommodates factory serpentine accessory brackets without modification.

Break-In Protocol Maintenance Duty Limits

Pre-lube engine oil passages with 5W-20 or 5W-30 synthetic blend oil using an external pressure reservoir before starting the engine. Bleed cooling jackets through the radiator and block drain plugs to expel air pockets. This engine package is not engineered for centrifugal supercharging exceeding 6 PSI on stock ring gaps or raw marine sea water cooling.

• Drain initial break-in motor oil after the first 50 road miles.
• Renew synthetic motor oil every 3,000 miles or six months.
• Inspect dual spark plugs and ignition coil boots every 12 months.

Warranty Coverage Pallet Crate Manifest

A 12-Month limited warranty protects against material and manufacturing defects. The banded wooden pallet crate houses the truck base long block, aluminum cylinder heads, dyno test certification sheet, and step-by-step installation guide. Components arrive sealed in vapor-barrier plastic wrap to prevent oxidation during storage and transit.