Question on milling heads

[baileyem]

I need some advice before I run down to the local machine shop to have the kinks and gouges taken out of my A4 engine head: How much meat can be taken from the face of a head before it is too much???

Or, what is the maximum amount that can be removed from an A4 head before the head becomes junk?

Anyone??

Mike

[thatch]

Mike,
The correct answer and I feel most A4 builders will agree is, as little as you can get away with. The main area of concern is the portion directly under the thermostat (in late model heads). I just measured my spare head and that area was only .125" thick. The critical areas of sealing are the narrow spots between each of the cylinders.
Tom

[baileyem]

Tom,
Thanks for the quick reply. I should have specified that mine is an early model and I dont have to worry about the area under the thermostat.
I guess what I am actually worried (wondering) about is, when will the valves run out of operating clearance? Or will they?

Mike

[ndutton]

I guess what I am actually worried (wondering) about is, when will the valves run out of operating clearance? Or will they?

And at what point do you change (increase) the compression? Likely not significant but had to ask.