ATK HP101M Chevy 383 Stroker Mid Dress Engine 460HP

The ATK HP101M sits between ATK's bare and fully dressed 383 stroker builds, carrying the same 460-hp, 490-lb-ft rating as the base engine but with a step more hardware already in place.

What mid-dress means here

This build's rotating assembly, a Scat nodular-iron crank and Scat I-beam rods, uses ARP 8740 rod bolts, under forged 10:1-compression pistons and the same Dart SHP aluminum heads as the base engine, 72cc chambers with valves at 2.02/1.60. The balancer, intake manifold, and distributor ship installed here, along with the OE-style water pump. The carburetor and fuel pump remain on ATK's recommended list for the installer, along with the ignition's spark plugs and wires.

What to check before you buy

• As with ATK's other big-cam 383 builds, this one will not pull the vacuum a power-brake booster needs.
• Confirm the exact intake and distributor brand with us before ordering.
• A set of roller rockers and a double-roller timing chain finish out the valve gear.

Common questions

Is the carburetor installed? No, only the intake, distributor, balancer, and water pump are installed on this mid-dress build.

Will it work with power brakes? No, this cam is not expected to supply enough vacuum for one.

What's the power rating? 460 hp, 490 lb-ft, the same numbers as ATK's base version of this engine. California requires BAR compliance for engine swap installations.