splayed valve aluminum

SMALL-BLOCK SPLAYED-VALVE ALUMINUM RACE CYLINDER HEADS

12480146

ROUGH-MACHINED SPLAYED-VALVE ALUMINUM CYLINDER HEAD 

  • Main surfaces are machined, exhaust bolt pattern is machined
  • Head bolt and dowel holes, intake bolt holes, spark plug holes, and pushrod holes are not machined
  • Valve guides, valve seats, valve spring seats, and rocker stands are not machined
  • Valve locations and angles may be relocated
  • 240-cc “as-cast” intake ports
  • 78-cc “as-cast” exhaust ports
  • 45-cc “as-cast” combustion chambers

12480147

SEMI-MACHINED SPLAYED-VALVE ALUMINUM CYLINDER HEAD

  • Main surfaces are machined; exhaust bolt pattern, valve guides, and spark plug holes are machined
  • Head bolt holes, dowel holes, intake bolt holes, and pushrod holes are not machined
  • Valve seats, spring seats, and rocker stands are not machined
  • 240-cc “as-cast” intake ports
  • 78-cc “as-cast” exhaust ports
  • 45-cc “as-cast” combustion chambers
  • Same casting as P/N 12480146

24502517

SPLAYED-VALVE ALUMINUM CYLINDER HEAD 

  • Semi-machined aluminum race head
  • 240-cc “as-cast” intake ports
  • 78-cc “as-cast” exhaust ports
  • 45-cc “as-cast” combustion chambers
  • Same casting as P/N 12480146

12480153

SPLAYED-VALVE 4.500 BORE CENTER ALUMINUM CYLINDER HEAD

  • Semi-machined aluminum race head
  • Great for drag racing competition with dual carburetors
  • As-cast ports and combustion chambers for professional finishing
  • Use mid-deck block with 4.500" main bore machining
  • Special larger head-bolt pattern, 3/8" fasteners, 19 holes
  • 240-cc “as-cast” peanut intake ports
  • 78-cc “as-cast” peanut exhaust ports
  • 40-cc “as-cast” combustion chambers

88958684

SPLAYED-VALVE 4.500 BORE CENTER ALUMINUM CYLINDER HEAD CUBED

  • Great for drag racing competition with dual carburetors
  • 240-cc “as-cast” peanut intake ports
  • 78-cc “as-cast” peanut exhaust ports
  • Cubed aluminum race head
  • Bare head, no seats or guides

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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.

  • 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.