If those are 5 or 6" crossbeams you can put 3 fully dressed 1HZ's on each shelf no sweat.
I have a section of 3" square upright 30" teardrop racking with 5" double wrapped beams currently carrying four complete 5.9 and 6.7 24 valve Cummins engines, a 6.0 Powerstroke and a 6.7 Powerstroke on two...