ATK HP101 Chevy 383 Stroker Base Engine 460HP

ATK's HP101 is a base-spec long block built from the 383 stroker platform, rated at 460 hp and 490 lb-ft of torque with a notably larger cam than ATK's milder 383 offerings, which pushes the output well past the brand's entry-level stroker engines.

Who this engine suits

A nodular-iron Scat crank spins Scat's I-beam rods, held together with ARP 8740 bolts, under forged pistons at 10:1 compression. Dart SHP aluminum heads, 72cc combustion chambers, carry valves sized 2.02/1.60. As a base long block, the intake, carburetor, distributor, water pump, and balancer stay on ATK's suggested parts list rather than being bolted on.

What to check before you buy

• ATK notes this cam will not pull enough vacuum to run power brakes, so plan another braking setup.
• A double-roller timing chain, a Melling standard-volume oil pump, and a set of 1.6-ratio roller rockers round out the valvetrain.
• ATK's recommended stall-speed converter for this combination runs 2,500 RPM or higher.

Common questions

Will this work with power brakes? No, ATK says the cam here will not pull enough vacuum for that.

Is the carburetor included? No, only the long block ships; induction and ignition stay on ATK's suggested list.

What heads does it use? Dart SHP aluminum, 72cc chambers, 2.02/1.60 valve sizing. California requires BAR compliance for engine swap installations.