These 350 "CNC" blocks are designed for NASCAR series racing. Main bearing torque specifications for all Bow-Tie blocks are 65 lbs. inner bolts, 60 lbs. outer bolts and 40 lbs. on 3/8" front bolts with light oil. They are light weight with the following specifications: CNC machined; 2.64" crankshaft diameter; 9.025 deck height; Bulk heads machined at 5 degrees; Special steel main caps; 6AN water drain; 45 degree -10 AN fitting front oil feed; 4 center valley drains drilled & tapped; Steam holes between cyl .0750 from deck; 4.115" bore diameter; 2.28" camshaft diameter; .875 lifter bore diameter; AN o-ring plug replacement pipe plugs; 1/2" NPS water hole each side of block; 45 degree -10 AN fitting valley scavenge; No oil hole boss.