Wow, yesterday one of the 915 heads cracked an exhaust port seam after 10 minutes on the dyno. We drilled some holes in the head between the intake and exhaust spring seats and both the intake and exhaust port walls looked like salt crystals. Crappola casting and on to the scrap pile it went. Cody cleaned up the bowls on some 906 heads and we used the valves from the 915's and slapped the engine back together today. Lots of other things scheduled for next week.....but maybe.