Racing Flag

PARTS INTENDED FOR COMPETITION USE ONLY.
Click for more details.

Racing Flag

PARTS INTENDED FOR COMPETITION USE ONLY.
Click for more details.

BIG-BLOCK PRODUCTION BASED BLOCKS

19170538

427/454 BARE BLOCK

  • New design casting incorporating the best designs of Mark IV and Gen VI
  • Production type cast-iron 4-bolt block  
  • 4.250” finished bore  
  • 4.310” max bore (non-siamese bore)   
  • Machined fuel pump pad  
  • New water jackets for use with Mark IV or Gen VI heads 
  • Revised oiling to allow for bigger cam bearings/cam lift
  • Bolt boss (not machined) added near distributor hole like 8.1L
  • Can be drilled for use with 10-bolt front timing cover 
  • Additional clearance added for roller timing chains   
  • Auxiliary oil pressure line added to front of block  
  • Racing-style oil filter cast feature with added oil pressure port
  • Additional boss for manual-transmission clutch pivot (machined)
  • Additional material added around lifter bosses  

19170540

502 MARK-IV/GEN-VI BARE BLOCK

  • New design casting incorporating the best designs of Mark IV and Gen VI
  • Production-type cast-iron 4-bolt block  
  • Improved main bearing bulkheads-Bowtie block-style bulkhead
  • Clearanced for bigger strokes 
  • 4.470” finished bore 
  • 4.600” max bore (siamese)  
  • Fuel pump pad has been added/machined 
  • New water jackets for use with Mark IV or Gen VI heads
  • Revised oiling to allow for bigger cam bearings/cam lift  
  • Bolt boss (machined) added near distributor hole like 8.1L 
  • Can be drilled for use with 10-bolt front timing cover  
  • Additional clearance added for roller timing chains   
  • Auxiliary oil pressure line added to front of block  
  • Racing-style oil filter cast feature with added oil pressure port
  • Two bosses added for manual transmission clutch pivot (machined)
  • Additional material added around lifter bosses

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.