How do you make a Hemi a "High Output" one?  (Especially one that'll make 590 horsepower out of the box?)

Come on inside & find out how Ma Mopar did it!

Mopar's introduced a more powerful, new crate version of the Gen III 426 Hemi V-8.The Gen III High Output Hemi engine, with 590 horsepower on tap out of the box, is now available under part number P5156139.

Starting with a lightweight aluminum block that shaves more than 100 pounds from the cast iron version, the Gen III High Output Hemi is professionally built and includes a stout, balanced lower reciprocating assembly that features a forged steel crankshaft with six-bolt mains at 2, 3 and 4, and cross-bolted 4-bolt mains at 1 and 5. H-beam style rods are forged steel, and coupled to forged 11:1 compression ratio
aluminum pistons. Included is a revised windage tray to provide excellent oil dispersion, and prevent oil aeration by the crankshaft.

The valvetrain starts with a more aggressive roller camshaft with .639-inch intake and .628-inch exhaust lift and cylinder heads that feature the latest designs for exceptional flow characteristics.

To help stabilize the valvetrain at high engine rpm, tie bars are available.
Cast aluminum valve covers and billet fuel rails also are part of the Gen III High Output engine.

Designed to run on premium pump gas with a minimum octane rating of 93, the newest Hemi V8 is ideal for off-road competition, or the latest restoration or resto-mod project.

Mopar also is offering two 426 Ready-to-Run engine control/base calibration kits, one for the High Output engine and one for the existing 426 crate engine.Kits include a throttle body, engine harness and engine controller with base cal. These kits greatly reduce guesswork, and will get your projects up and rolling.

Depending on transmission type, axle ratio, and tire size, some final tuning may be required.

 

(Courtesy Mopar)