I have a 230 that has been cross drilled. I had a machinist do it for me. I do not remember exactly how he did it. The crank has to be cross drilled at the #2 and #3 mains. Those mains has to supply oil to 2 rods each, where #1 and #4 only supply one rod each. This is why most all rod burn out's occur at 2,3,4,5 rod bearings. I do remember that there are 2 holes in the crank passing the main hole to supply oil to those rods. I also remember that the holes in the main bearings don't align well with the hole in the block. They need to be matched up to get full flow of oil. The oil groove in the main bearings are very shallow. They need to be made wider and deeper. My engine holds over 80 lbs. of oil pressure. It will turn 6000 rpm's with no problem. It has been running 5 years now and is showings no signs of wear. Checked rod bearing after the first couple of years. They showed no signs of wear.
Hope this helps.
