Is it a big small block, or a small big block Chevy? Whichever way you look at it, the new 4.840 bore spacing block from PBM Performance Products combines the ability to take standard big block heads with the ability to accept standard small block parts like the water pump, fuel pump, and distributor. The big block bore spacing means more room for all the internal components without clearancing – the maximum bore size is 4.550″,  and clears up to a 4.250″ stroke. The block is available with 350 or 400-sized main journals, and it also features a raised, modified cam tunnel, 9.000 to 9.600 deck heights, a dedicated main oil system, ARP hardware, splayed center main caps, and a 6-bolt rear main cap.

• Stretched SBC capable of upwards of 560 cubic inches
• Made of proprietary 356 T-7 aluminum
• Features 4.840″ bore spacing and enlarged cam tunnels
• Standard SBC water pump, fuel pump, and distributor bolt right on
• Compatible with any Big Block Chevy cylinder head