12-7-2007 This is the part of the project where it looks it’s worst, but it looks worse than it is. The beauty of the design of an engine is that most stuff doesn’t actually have to be all that precise. The bores have to be round and to size, but machines are good at round holes so that’s pretty easy to get right and since the 348 liners are bigger diameter than the 400 liners (in most places) there is matal to cut to make then round. If the bore position is off a full mm in any direction it wouldn’t be ideal, but the engine would still run just fine, it's not all that important, but I'll be able to get them within a couple thousandths of an inch without all effort at all.
You’re right that most of the cylinder is no longer a cylinder, but the bottom inch or so is untouched and right where ferari put it. I can either bold the block flat on the machine and tip the head to 30 degrees or I can trip the block to 30 degrees. It’s an easier and stronger set-up to tip the machine, but then I have to trig all the y direction movements when I start drilling the stud and pin holes. Anyway, after I pick a set-up I’ll indicate the crank journals parallel. Then I just need to put a dial indicator in the spindle and center up on what’s left of the bore, throw in the boring head and cut the hole round again. I’ll record the location of all the bore centers and use that information to decide where to drill the head studs and pin holes.
I’m planning to use the 348 liners, which are bigger than the 400 liners so I have metal to remove and that will make the clean-up much easier. Cutting metal out is easy, putting it back is a pain. The problem at the moment is that I don’t actually have the liners so I have no idea what size to cut anything. For now I’m just going to cut off the heavy weld and get back close to the original 400 size at the bottom and QV liner (I have those) size up top. I want to do the finish liner bores after the block is final decked anyway so I know how deep to cut the holes.
There is a solid day of rough machining I think (which probably means 2 days), but I should have the heads on the block this weekend and be on to the timing chain and cover issues. At that point is will start to look a lot more like there is any hope of it ever running again.
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