ATK High Performance GM 350 330 HP Stage 1 Long Block Crate Engines HP291P

Buy ATK High Performance GM 350 330 HP Stage Online

Bring your small block Chevy back with stronger street power using the ATK High Performance GM 350 Stage 1 Long Block (HP291P). Rated at 330 horsepower, this 350ci crate engine is built around a seasoned OE 4-bolt-main, one-piece rear main seal block and matched components designed for reliable torque and crisp throttle response. Inside, a 4.040 in. bore and 3.480 in. stroke combination uses hypereutectic pistons and moly rings for durability and consistent sealing. A hydraulic flat-tappet camshaft and double-roller timing set deliver an aggressive, street-friendly profile while maintaining vacuum for atk 350 crate engine power accessories. Cast-iron cylinder heads with 1.94/1.50 in. valves help the blueprint 383 engine breathe efficiently, and stamped 1.5:1 rockers keep valvetrain service simple.

This long block arrives assembled and ready for your choice of intake, fuel, ignition, and front dress to match your vehicle or marine conversion needs. Every unit is precision-machined, carefully assembled, and inspected so you can swap it in with confidence and get back to enjoying that classic 350 sound and feel. Designed with internal front and external rear balance (per OE-style components), it’s an ideal foundation for hot rods, trucks, and classic muscle builds where you want dependable horsepower without the complexity of a dressed engine package.

ATK High Performance GM 350 330 HP Stage 1 Long Block Crate Engines

Give your ride new life with ATK High Performance GM 350 330 hp/380 lbs.-ft. Stage 1 long block crate engines. These engines are based on the tried-and-true small block Chevy and are built to perform right out of the box. ATK hand-assembles and balances each engine using top-quality parts to help them produce awesome power. Whether you are replacing an older, worn down engine or just looking for a little more performance, ATK has you covered.

Stage 1 long block crate engines include:

* Handpicked, remanufactured blocks
* ATK cast iron cylinder heads
* 76cc chambers
* 165cc intake runners
* 1.94 in./1.5 in. valves
* Stamped steel 1.5 ratio rocker arms
* OE crankshaft
* OE 5.7 in. powder metal connecting rods
* Hypereutectic flat-top pistons
* Moly rings
* Hydraulic flat tappet camshaft
* 465 int./.488 exh. cam lift
* 224 int./234 exh. cam duration at 0.50
* 9.1:1 compression
* Valve covers
* Timing cover and timing set
* Oil pan, pump, and pickup tube

What’s included with a “long block” crate engine?

A long block typically includes the assembled block, rotating assembly, camshaft/valvetrain, and cylinder heads (often with covers and oiling components). It usually does not include intake, carb/EFI, distributor, or accessory drive—confirm the exact included parts on the product page.

Will this engine fit my application?

It’s intended for Gen I Chevy small-block 350-style setups. Fitment depends on your oil pan clearance, mounts, flexplate/flywheel balance, and accessory configuration—verify these against your vehicle (or marine) application before ordering.