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Mopar Performance Cast Iron Engine Blocks & Components - Small Block


Mopar Performance
Mopar Performance Cast Iron Engine Blocks & Components - Small Block

These blocks are made from high strength cast iron and are heavy-duty pieces with extra stock for improved strength. All of the blocks include 4-bolt main caps on the center 3 caps (with ARP main cap bolts). Most of the blocks come with a Siamese bore water jacket and some have the full water jacket. The 48° tappet bore blocks come with a 6-bolt cylinder head bolt pattern. The 59° blocks have a 4-bolt pattern for the cylinder head.

This package includes the engine block assembly with main caps, main cap fasteners, and the block hardware kit. Some of the block hardware is installed in the block and some is included in a separate package with the block.

The R3 and R4 blocks are designed for use in racing where the engine builder does most of the final machine work (i.e. boring, honing, and camshaft bearing installation).

The 340 Replacement and Magnum Blocks are designed for customers who assemble the engine in their own workshop (i.e. blocks are honed to standard bore size, and the cam bearings are installed). Made in the USA.


9 Products
340 Replacement Blocks
  • 59° Tappet Bore
  • Deck Height 9.600"
  • 318/340 Mains
  • Main Caps - 4-Bolt Center 3 Caps - Ductile Iron

  • 312-P5007552AB
    340 Replacement Block
  • Non-Siamese Bore Casting
  • Casting # 2780930M
  • Works with Most Stock Style Small Block Parts (1964-1992)
  • Cam Bearings Installed - Stock OEM Style
  • Bore - Honed to Stock 340 Size 4.040"
  • $119
    $3,107.99
    Order Today Ships 11/03/14
    R3 Race Blocks
  • 318/340 Mains
  • Siamese Bore Casting

  • 312-P4876381AB
    R3 Race Block
  • Casting # P4532907
  • 48° Tappet Bore, Must use Race Heads
  • Deck Height: 9.025"
  • Main Caps: 4-Bolt, Center 3 Caps - Billet Steel
  • Dry Sump Oiling System Only
  • Cam Bearings Not Included.
  • Rough Bored to 4.050"
  • $119
    $3,105.99
    Order Today Ships 11/03/14
    R4 Race Blocks
  • Siamese Bore Casting
  • 2.25" Mains (302 Ford Main Bearings) - Requires Custom Crank
  • Main Caps: 4-Bolt, Center 3 Caps - Billet Steel
  • Deck Height: 8.575"
  • Dry Sump Oiling System Only
  • Cam Bearings - Not Included - Must use 60mm Roller Cam Bearings P5007361 & Custom Cam
  • Rough Bored to 4.050"

  • 312-P5007151AC
    R4 Race Block
  • Casting # P4532982
  • 45/59° Tappet Bores - Must use P5 or P5 Hemi Cylinder Heads
  • $119
    $3,654.99
    Order Today Ships 11/03/14

    312-P5007270AC
    R4 Race Block
  • Casting # P4532982
  • 48° Tappet Bore - Must use Wedge (W8 or W9) Style Race Cylinder Heads
  • $119
    $3,768.99
    Order Today Ships 11/03/14
    Cam Bearings
      312-P4876372
    48º Camshaft Bearing Set
  • Material: Babbit
  • Fits Small Block Race Blocks w/ 48º Tappet Bores
  • Use w/ Custom Race Camshaft
  • Fits: Blocks 312-P4876671AD & 312-P4876673AD
  • Does Not Fit OEM or Blocks w/ 59º Tappet Bores
  • $93.99
    Order Today Ships 11/03/14

    312-P4876707
    Roller Cam Bearing Set
  • Material: 50mm Roller Bearings
  • For SB Race Block w/ 50mm Cam
  • Use w/ Custom Race or Unground Lobe Cams 312-P5007932 / 312-P5007134
  • Fits Block 312-P4876381AB
  • Does Not Fit OEM or Blocks w/ 59º Tappet Bore
  • $152.99
    Order Today Ships 11/03/14

    312-P5007361
    A4 Cam Bearings
  • Fits A4/R4 Blocks w/ W9/W9RP/P5/P5 Hemi Cylinder Heads
  • Fits 60mm Journal on Cam
  • Roller Bearings - Set of 5 Pieces
  • $176.99
    Order Today Ships 11/03/14
    Camshaft Cores - Unground Lobe
      312-P5007134
    R3/Aluminum "A" Cam Core - UGL
  • Fits R3 Block 312-P4876381AB w/ 50mm Roller Cam Bearings & 48º Tappets
  • Fits Aluminum "A" Blocks
  • Unground Lobes (Requires Custom Grind to Your Specifications)
  • 50mm Journals
  • 8620 Steel
  • $459.99
    Order Today Ships 11/03/14
      312-P5007437
    R4 Cam Core - UGL
  • Fits R4 Block 312-P5007270AC
  • Unground Lobes (Requires Custom Grind to Your Specifications)
  • 60mm Journals
  • $366.99
    Order Today Ships 11/03/14

    9 Products