My brother came over we set the cutting bits up as close as we can until we get a dial indicator setup for this task. Decided to make another test cut on the manifold surface of the Minneapolis Moline ZA cylinder assy. The new bits cut way better than the old dull one's. Its actually plenty good to use as is but we will still try to dial it in some more. We then tried a Ford 351 Cleveland head to see how it worked on a longer cut. Worked great on that head also.