ATK SP04 Chevy 350CI Short Block Flat Top Pistons Engine

Item #31975 Brand:ATK Engines

ATK SP04 Chevy 350CI Short Block Flat Top Pistons Engine
ATK SP04 Chevy 350CI Short Block Flat Top Pistons
* ** FREE SHIPPING on ATK Engines. This item ships directly from the manufacturer and is not available for store pickup. Some engines are made-to-order or can be backordered. Delivery can be delayed up to 5 to 6 weeks but typically ship within 2 weeks.
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This is a great foundation for a mild performance build or a good upgrade for a worn out short block. Your engine may not necessarily come with all components listed, but they are listed as our recommendations of parts to run for optimal performance.

Engine Specifications:

  • Block: OE roller block 4 bolt main 1pc seal 1996-2000
  • Bore/Stroke: 4.040” x 3.480”
  • Displacement: 350CI
  • Crankshaft: OE Reground external balance rear of the crank/internal balance front of the crank
  • Rods: OE powder metal 5.7”
  • Pistons: Hypereutectic -6.4cc flat top
  • Compression Ratios: 58cc = 10.9:1 / 64cc = 10.1:1 / 70cc=9.5:1 (can vary due to deck height/gasket thickness)
  • Rings: Plasmamoly
  • Camshaft Bearings: Dura-Bond, installed and clocked to OEM position
  • Freeze Plugs: Brass, installed and sealed
  • Oil Galley Plugs: Installed and sealed

Every great build needs a solid foundation! For that reason, we take the hard work out of the picture by selling short blocks that are ready for you to complete yourself. Our GM Short Blocks are most commonly packaged as the engine block assembled with Pistons, Piston Rings and Crankshaft installed.

ATK specializes in muscle. With the highest quality internal parts and Dyno Proven combinations of every engine built, ATK is able to add the most bang for your buck and back it up with an industry leading warranty.

Don't forget the engine paint!
Engine Paint


(1) ATK SP04 Chevy 350CI Short Block Flat Top Pistons


Engine Information:

• Oil: 10W30 Non synthetic for first 3000 miles
• Oil Filter: Wix or K&N per application
• Weight: 285 lbs.


Recommended Components: • Balancer: Internal balance
• Flexplate/Flywheel: External balance
• Head Gasket: .038” or per application

Shipping Instructions and Core Information

Shipping is free and lift gate will be provided.

There is no core charge for this engine. You will not be required to send a core back to the manufacturer.

Eastwood Offers Free Lifetime Technical Support

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