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Mopar Performance P4876381AB

R3 Race Block Casting # P4532907

Mopar Performance P4876381AB
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Estimated ship date 03/28/18 if Ordered Today
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Truck Freight: $119.00
Mopar Performance P4876381AB R3 Race Block Casting # P4532907 $2,870.99
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"

  • Mopar Performance P4876381AB Details

    R3 Race Blocks

  • 318/340 Mains
  • Siamese Bore Casting

  • Cam Bearings Not Included - Must use 50mm Roller Cam Bearings P4876707 & Custom Cam

    R3 race blocks are generally used in racing applications since some versions are designed for dry sump oiling systems, and some have shorter than stock deck heights. Some versions have the 48 degree tappet bores that must be used with racing cylinder heads (some W2, W8/W9 cylinder heads). These blocks now come with dual motor mounts - both "LA" 318 and Magnum style motor mounts. The short deck versions of these blocks require a special timing cover (P4876631 or P4876632). These blocks are typically used in Late Models, 360 sprint cars, and drag racing

  • Specifications:

    Rear Main Seal Style
    Cam Bearings Included
    Cylinder Bore as Shipped (in.)
    Cylinder Bore Diameter (in.)
    Deck Height (in.)
    Engine Block Material
    Cast iron
    Engine Block Style
    Finished Cylinder Bores
    Freeze Plugs Included
    Main Bearings Included
    Main Bolt Style
    Main Cap Fasteners Included
    Main Cap Material
    Main Caps Included
    Main Journal Type
    340 mains
    Sold individually
    Raised Cam Location
    Manufacturer's Part Number:

    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).

    Will this block accept the ascs mopar Sprint car heads

    Asked by: Donovan
    These heads should fit on this block.
    Answered by: Rusty B
    Date published: 2018-01-19

    Hi, this is a NEW block from Mopar Performance? or is remanufactured ?

    Asked by: V8arg
    According to Mopar this is a new casting.
    Answered by: Rusty B
    Date published: 2017-09-14
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