small block

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

CYLINDER BLOCK COMPONENTS

 

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FRONT COVERS, TIMING POINTERS,
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Unless specifically noted to the contrary herein, vehicles equipped with Chevrolet Performance Parts may not meet Federal Motor Vehicle Safety Standards and emissions regulations and should not be operated on public roads. Chevrolet Performance customers are responsible for ensuring their use of Chevrolet Performance complies with applicable federal, state, and local laws, regulations, and ordinances. Many parts intended for racing or other “off-highway” use are not designed or tested for crashworthiness or to meet the safety needs of the motoring public, and may adversely affect the original intended performance or handling characteristics of the vehicle. These parts are designed and intended to be used with experts supervising their installation and use, to help assure the proper and safe operation of the vehicle.

  • The Manufacturer's Suggested Retail Price excludes destination freight charge, tax, title, license, dealer fees and optional equipment. Click here to see all Chevrolet vehicles' destination freight charges.

  • EPA-estimated MPG city/highway: Sonic with 1.8L engine and 5-speed manual transmission 26/35; with 1.8L engine and 6-speed automatic transmission 25/34; with 1.4L engine and 6-speed manual transmission 28/37; with 1.4L engine and 6-speed automatic transmission 27/35.

  • Dependability based on longevity: 1987 – July 2017 full-size pickup registrations.

  • The Manufacturer's Suggested Retail Price excludes destination freight charge, tax, title, license, dealer fees and optional equipment. Click here to see all Chevrolet vehicles' destination freight charges.

  • MyLink functionality varies by model. Full functionality requires compatible Bluetooth and smartphone, and USB connectivity for some devices.

  • Do not use summer-only tires in winter conditions, as it would adversely affect vehicle safety, performance and durability. Use only GM-approved tire and wheel combinations. Unapproved combinations may change the vehicle’s performance characteristics. For important tire and wheel information, go to my.chevrolet.com/learn/tires or see your dealer.

  • With rear seats folded. Cargo and load capacity limited by weight and distribution

  • EPA-estimated 29 MPG city/39 highway with 5-speed manual transmission and 30 MPG city/38 highway with available Continuously Variable Transmission

  • EPA-estimated 29 MPG city/38 highway with 5-speed manual transmission and 30 MPG city/38 highway with available Continuously Variable Transmission.

  • Requires available Performance Exhaust or Z51 Performance Package.

  • Requires available Performance Exhaust or Z51 Performance Package.

  • If you decide to continue service after your trial, the subscription plan you choose will automatically renew thereafter and you will be charged according to your chosen payment method at then-current rates. Fees and taxes apply. To cancel you must call SiriusXM at 1-866-635-2349. See SiriusXM Customer Agreement for complete terms at siriusxm.com. All fees and programming subject to change. Sirius, XM, SiriusXM and all related marks and logos are trademarks of Sirius XM Radio Inc.

  • Before you buy a vehicle or use it for trailering, carefully review the Trailering section of the Owner’s Manual. The weight of passengers, cargo and options or accessories may reduce the amount you can tow.

  • EPA-estimated 28 City/39 Hwy MPG

  • With second row seats folded flat. Cargo and load capacity limited by weight and distribution.

  • The Manufacturer's Suggested Retail Price excludes destination freight charge, tax, title, license, dealer fees and optional equipment. Click here to see all Chevrolet vehicles' destination freight charges.

  • Read the vehicles Owner’s Manual for more important feature limitations and information.

  • Does not detect people or items. Always check rear seat before exiting.

  • Vehicle user interface is a product of Apple and its terms and privacy statements apply. Requires compatible iPhone and data plan rates apply. Apple CarPlay is a trademark of Apple Inc. iPhone is a trademark of Apple Inc., registered in the U.S. and other countries.

  • Vehicle user interface is a product of Google and its terms and privacy statements apply. Requires the Android Auto app on Google Play and an Android compatible smartphone running Android 5.0 Lollipop or higher. Data plan rates apply. Android, Android Auto, Google, Google Play and other marks are trademarks of Google LLC.

  • Service varies with conditions and location. Requires active OnStar service and paid AT&T data plan. Visit onstar.com for details and limitations.

  • Premier shown seats seven. Standard on L, LS. Available on LT.

  • EPA-estimated 18 MPG city/ 27 MPG highway 3.6FWD.

  • With second row seats folded flat. Cargo and load capacity limited by weight and distribution.

  • EPA-estimated 18 MPG city/ 27 MPG highway 3.6FWD.

  • Read the vehicle owner's manual for important feature limitations and information.

  • Chevrolet Infotainment System functionality varies by model. Full functionality requires compatible Bluetooth and smartphone, and USB connectivity for some devices.

  • The system wirelessly charges one PMA- or Qi-compatible mobile device. Some devices require an adaptor or back cover. To check for phone or other device compatibility, visit my.chevrolet.com/learn for details.

  • Read the vehicles Owner's Manual for more important feature limitations and information.

  • The Manufacturer's Suggested Retail Price excludes destination freight charge, tax, title, license, dealer fees and optional equipment. Click here to see all Chevrolet vehicles' destination freight charges.