Kebowers,
It sounds like you did your homework. By the way you probably know the difference between mechanical engineers and structural engineers. Mechanical engineers buil weapons, and structural engineers build targets. I think too many things like cylinder heads and rotors get machined for no reason in this country, because most mechanics don't know how to check tolerances. Everytime a job is done on a domestic piece of doo doo that involves stretch bolts, it gets new stretctbolts, because there are no specs available for domestic stretch bolts nor does anyone know how to measure them. I always reuse stretch bolts after I have measured them with a mic and checked the TDM. As you say, a slight warp can be tolerated especially when you see that each head uses 18 bolts. I didn't suface the heads on the 560SEC and 380SEL that I did in the last few years. I'm doing a valve job on a 380SEC right now, because it jumped timing andnot doing the heads, because they checked out with a straight edge and feeler gauge. The 560SEC I did came in months later with a tick in the left bank. I used a stethoscope to isolate the lifter and changed only the one lifter. You made a good point about the cam turning free. A good mechanic always checks the turning ease of things before finishing the job.

Peter

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