The $300.00 charge to line hone would be roughly $100.00 an hour. With the old, manual Sunnen LH-100 line hone it takes me 3 hours to get a Pontiac block dead nuts on. That would be +-.0001 through the 5 mains, 70% of the diameter, taper .0001". Factory tolerance is +-.0005. Even a marginal shop can hit that range. Used Pontiac blocks will generally fall into the factory tolerance range if the bearings are not damaged. It all amounts to your goals, your budget and your luck to some extent. I have lousy luck, a small budget, and high expectations. But I machine my own engines. Line hone is a fairly complex process. The exact hardware and torque specs. you are going to run must be considered. The caps must be cut parallel and square and even. The edges de-burred. When honing, shoe height must be adjusted exactly to avoid cutting too much out of the block. To get round and straight results, I generally have to flip the block end to end 4-5 times. This is all time consuming, oily, heavy work. Sonic testing, on the other hand is quick, fast and clean. If I was getting $300.00 to line hone a block, I would probably throw-in a sonic check free. Especially if I was doing other machining on the block. You can get 32 quick measurements, 8 cyl X4 in less than 1/2 hour on a clean block with a hand held Dakota sonic tester.
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