Here are the details of the Drag Week 572 B1 motor I built:

11.3:1 compression for pump gas and then 600-750 Nitrous

Diamond Pistons 1.32 compression height and 24.2cc dish, valve depth at 90* intake: 330 and exhaust 270 picture of card and order form below

Cam designed by Monte Smith for this motor: .824/.789 lift with 1.75 pair T&D rockers (.471/.451 lobe lift), 279/294 duration, 112 Intake center line, 115 lob separation cam card pic below

I didn't write down the exact minimum clearance because I had more than .150 at 10 before and 10 after. Since we had a Jessel belt drive and we could adjust the cam degree easliy we did check it at a few different places but left the cam installed at 112.

For my pistons we didn't spec the valve pockets, we just used an off the shelf piston part #, changed the ring pack and told them to adjust valve pockets for B1 heads but they were supposed to keep the 4cc to keep 12:1 compression target. I'm guessing they may need to put a little dome on top side of the piston or they may want to decrease compression height from 1.480"