Not much NateDogg.
All I've seen is blurb form Mike Mulhern and virtually the exact same reference somewhere else but I can't remember where. Have no yet had the cahnce to really search out any additional info, if any is available.
From Mike:
Dodge teams are now running a new, lighter engine block, according to Detroit sources - 30 pounds lighter, a significant change. The block was reportedly cast by Caterpillar. How the weight might have been trimmed is unclear. When Dodge brought its first block into Winston Cup racing, the block had wide bore spacings, which meant that Dodge teams could run more RPMs. Rivals complained, and in July, Dodge teams had to start running with narrower bore spacings, which put them at a disadvantage of an estimated 40 pounds. It is unclear when NASCAR might have okayed the change.