How much hp/w2

436” X block. W2 heads, tunnel ram, 13.1 compression, 668 lift solid roller, 1-7/8” headers. It made 652 hp at 6900 rpm. 590 tq at 4800 rpm on the dyno that day in that room.

this is my current W2 headed small block,

You got me beat by 28 cubes , 2.5 points of compression and probably a few degrees of duration.