[performerrpm]

what is it for? i didnt notice until a few days ago that the ia2 i bought just recently has a few differences aside from the serial numbers being up in front. this one has a solid lifter bore while the new one has small holes in the middle of the lifter bore. after a closer look i realised the main caps on this one is not registered but i was sure they were on the one i just bought new a couple years back. so i dug it out and seen it has registered caps and in the finishing kit it has a spacer for the timing cover to oil pan. is that needed for all ia2s or just the newer ones? i just assumed the saddles were machined into for the caps but this makes me think the rails must be raised?