Ok here are the specs on the motor. It is a 4 bolt billet main block. Is a roller block with acl ceramic bearings in it still. It is bored .040 over and is clearanced to handle a 3.875 stroke crank. All oil passages have Ben drilled and tapped and plugged and has been setup for optimal oil flow. It is originally a 1 piece rear main block but has a 2 piece adapter plate that comes with it. Has a melling high volume oil pump and arp main studs on it. It's in great condition and will be pick up only. I have pictures I can email you if interested.