This is a bare race block sold deliberately unfinished. It arrives bored to 4.120 in. so your machinist can hone to final size with the intended piston and ring package in hand, which is how clearances actually get controlled on a serious build. The tall 9.76 in. deck gives room for a longer rod ratio, and six-bolt main caps hold the crank under load a production block would not survive.

Edelbrock 54901U LS Race Block Specifications:

• Aluminum LS race block, eight cylinder.
• Tall deck at 9.76 in. deck height.
• Cylinder bore 4.125 in. as machined, listed for honing to 4.120 in.
• Six main bearing cap bolts per cap.
• Supplied bored and ready to hone, so final machining is required before assembly.