I assume the loss of compression would be due to the slightly larger volume of the combustion chamber. Given that pressure decreases proportionately with increase in volume, I would guess that the compression would be decreased by about 0.0002%....is this correct, or am I missing something.

Is there some other critical problem having to do with less mass (thinner) on the valve itself, or limitations on adjusting valve clearances??

While I would rather have new exhaust valves rather than re-ground ones, I dont know if I really need to return the head for something better. I would like to get another 250,000 miles out of the car, as everything else has been maintained in tip top shape and restored. The only consequence of having re-ground exhaust valves may be that the next time I need a valve job, I wont be able to re-grind them....I will then need new ones. However, as long as I adjust valve clearances, valves shouldn't burn and I should get another 250K out of the car without more head work. Is this correct?

Anyone out there agree? Disagree?


Thanks to all for lots of help,

Mark

__________________
1984 300TD Wagon, 407,800 mi (current daily driver)
1985 300DT Sedan, 330,000 mi (gone to that great autobahn in the sky)