Block Machining
 

Anyone who has done any machining on a Cummins block, have you ever upgraded the oiling passages at all? I know on some V8 motors it helps a lot with oil distribution. Also, how big can you make the cylinders before hitting water? What is the largest you can make the cam tunnel also? I haven't got a hold of a block yet myself to check all this out, but am planning to very soon.