Description
ATK HP89C 350ci Chevrolet crate engine — 390 hp / 420 lb-ft
The ATK HP89C is a 350-cubic-inch small-block Chevrolet V8. ATK lists output at 390 hp and 420 lb-ft. The engine uses a 1996–2000 OE roller block with four-bolt mains and a one-piece rear main seal; bore and stroke are 4.040 × 3.480 inches, and compression is 10:1. Specifications below follow ATK’s published HP89C listing.
Listed components
- Hydraulic-roller camshaft
- ATK aluminum cylinder heads with 64cc chambers
- Dual-plane intake
- Quick Fuel 670-cfm vacuum-secondary carburetor with electric choke
- HEI distributor and mechanical fuel pump
- 5-quart rear-sump oil pan
- Externally balanced flexplate/flywheel and internally balanced balancer
Fitment notes
ATK says the oil pan is not suitable for Chevelles with steering behind the crossmember, some Corvettes, or 1962–67 Chevy II models. Its recommendations include 91+ octane fuel, a 2,200–2,800-rpm stall converter and 1⅝-inch headers. ATK notes that power figures can vary with the supporting parts used and that buyers are responsible for confirming application compatibility.
Verify oil-pan clearance, mounts, accessory drive, transmission, exhaust, fuel and cooling requirements before ordering. Contact us with the vehicle year, make, model and intended use if you need help checking fitment.
