SMALL-BLOCK
BLOCKS AND
COMPONENTS

SMALL-BLOCK
BLOCKS AND
COMPONENTS

Where winning begins

Build for the street, the strip, or both with power factory-engineered to compete.

PRODUCTION-BASED BLOCKS

When building a performance engine or replacing a stock engine, our production-based blocks offer the strength, accuracy, and peace of mind you’d expect from Chevrolet Performance.

Production-Based Blocks Technical Notes

  • Standard 350 main journal sizes
  • Non-Siamese bores
  • Production-spec cylinder wall thickness
  • Lifter valleys machined for hydraulic-roller and flat-tappet valvetrains  

BOWTIE SPORTSMAN BLOCKS

These highly versatile blocks are available in a variety of finish options for maximum flexibility, providing a rock-solid foundation for any drag strip, circle track, or high-performance application in the 300-500-horsepower range.  

Bowtie Sportsman Technical Notes

  • Standard 9.025-inch deck height
  • Nominal cylinder wall thickness is 0.340-inch
  • Minimum cylinder wall bore thickness on 4.155-inch bore is 0.225-inches (excluding P/N 10051181, 10051183, and 10185047)
  • Extra-thick deck surfaces have blind-tapped bolt holes for improved head gasket sealing
  • Priority main oiling system
  • Main bearing bulkheads are 0.900-inch thick and use Grade-8 bolts
  • All five cam bearing locations require 2.000-inch O.D. (1.867-inch I.D.) bearings P/N 12370843 (except block P/N 10051183)
  • Tall lifter bore blocks may require clearancing the top of the lifter bores for some roller lifters
  • Lifter valley oil scavenging boss below bell housing flange is present, but not drilled and tapped
  • Oil dipstick holes are not drilled
  • Timing system clearance must be checked

RACE BLOCKS

From start to finish line, precision is the operative word with high-grade materials and machining techniques, and proven stock Car and drag racing performance heritage.   

Race Block Technical Notes

  • Precision CNC-machining means +/- 0.001-inch tolerances.
  • Cylinder bore wall thickness is 0.225" minimum at 4.155" bore. A sonic bore check data sheet is provided with block
  • Nominal wall thickness of cylinder bores is 0.340"
  • Cylinder decks, front and rear of case, oil pan rail surfaces and head dowel pins are blueprinted
  • Extra-thick deck surfaces have blind-tapped head bolt holes for superior head gasket sealing
  • Enlarged cam bosses allow custom machining for larger bearings
  • Non-standard cam bearings are required (see each block for details)
  • Extra-thick main bearing bulkhead is machined at 5°
  • Bearing cap inner bolts are spread 0.210" to allow machining for 400 journal crankshafts
  • Premium quality main studs and SAE 8620 steel main bearing caps
  • Priority main oiling system
  • Billet wet sump rear main cap can be adapted to dry sump with plugs
  • 2-piece rear main crankshafts and pre-1986 oil pans are required
  • Use of some aftermarket mechanical roller lifters may require clearancing top of lifter bores
  • Timing system clearance should be checked before engine assembly
  • Lifter valley oil scavenging boss below bell housing flange is not drilled or tapped
  • Oil dipstick holes are not drilled

ALUMINUM RACE BLOCKS

Aluminum race blocks provide competition-level strength and reliability for road racing or high horsepower turbocharged applications.

Aluminum Race Blocks Technical Notes

  • Extra-thick deck surfaces with blind-tapped head bolt holes for improved head gasket sealing
  • Centrifugally spun cast-iron cylinder sleeves
  • 2-piece rear-main crankshafts and pre-1986 oil pans required
  • Enlarged cam bosses allow machining for larger cam bearings
  • 2.000" O.D. (1.867" I.D.) cam bearings P/N 12370843 required
  • Blocks may require clearancing at top of lifter bores (0.842") for some roller lifters
  • Timing system clearance should be checked before engine assembly
  • Extra-thick main bearing bulkhead machined at 5°
  • Premium main studs and steel main bearing caps
  • Priority main oiling system Billet wet sump rear main cap can be converted to dry sump with plugs
  • Oil dipstick holes not drilled

CYLINDER BLOCK COMPONENTS

Learn More

FRONT COVERS, TIMING POINTERS,
FUEL PUMP BLOCK OFF-PLATE

Learn More

CYLINDER BLOCK COMPONENTS

FRONT COVERS, TIMING POINTERS,
FUEL PUMP BLOCK OFF-PLATE

Email Sign-Up 


Subscribe to receive monthly email communications such as news, offers, and more from Chevrolet Performance.

The BLOCK


Visit TheBLOCK.com for a behind-the-scenes look at the world of Chevrolet Performance from an enthusiast's point of view.

Connect


Connect with Chevy Performance.

Email Sign-Up 


Subscribe to receive monthly email communications such as news, offers, and more from Chevrolet Performance.

The BLOCK


Check out Chevrolet Performance product releases, future car builds, and more.

Connect


Connect with Chevy Performance.

VISIT OUR BRANDS FOR YOUR OE NEEDS

|

Unless specifically noted to the contrary herein, vehicles equipped with Chevrolet Performance parts that are emissions-related may not meet U.S., Canadian, and state and provincial laws and regulations relating to motor-vehicle emissions. These parts are designed and intended for use in vehicles operated exclusively for competition: in racing or organized competition on courses separate from public streets or highways. Visit www.chevroletperformance.com/emissions for more details.