19170540 502 Mark IV/Gen VI Bare Block

• New 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