ATK HP96 Chevy 383 Stroker Marine Base Engine 380HP

Marine duty is the whole point of the HP96, a 383 stroker good for 380 hp and 445 lb-ft of torque, built around Dart SHP aluminum heads rather than the cast iron Vortec heads used on ATK's other marine 383. It ships as a base long block, leaving intake, carburetor, and ignition to the installer.

Marine-grade recommendations

ATK's suggested induction for this combination is a Weiand Stealth dual-plane intake with a marine-grade carburetor in the 650 to 680 CFM range, a marine-grade distributor with an iron gear, and a Holley mechanical fuel pump rated at 110 gallons per hour. None of these ship installed; they are ATK's suggested components for the application.

Inside the long block

A 4.040-inch bore and a 3.750-inch stroke add up to 383 cubic inches. Dart SHP aluminum heads run 1.5-ratio rockers finished in stamped steel, feeding hypereutectic pistons at 9.1:1 compression. The crank and rods come from Scat, nodular iron up front and I-beam rods below, both fastened with ARP hardware. ATK recommends 91 octane fuel once the engine is in service, and the base-dress approach leaves the carburetor, intake, and ignition choice up to whoever installs it.

Q: Does this include a carburetor or distributor? No, both are ATK's recommended parts for this build, sold separately.

That leaves real flexibility in how the rest of the induction side comes together, since none of ATK's suggested parts are locked in.