QUOTE(pgollender @ May 20 2017, 11:11 AM)
"They must be cored and driven out from the camber side, then see if they are salvageable."
Can you explain this comment a little more.
I understand the part about cored and driven out, but not the "salvagable" part of your comment.
I have never rebuilt 914 heads personally before, always had a machine shop do it for me.
The boss surfaces and intake surfaces look intact (no magnaflux test) . I can't see any visible cracks between intake and exhaust ports or to spark plug hole.
The current guides appear to be quite tight,and I can elicit no guide wobble within the bore itself.
Not sure how to test the angle of the guide.
Is there another step that requires evaluation of the guide bore hole that you are referring to ?
Also what is the correct finished height of the guides above the boss surface once installed ?
Just take it to your machine shop, preferably one with aircooled engine knowledge.
As Len (HAM) said guide slippage and I said guides are sunk deeper than normal, so the guide must be removed, reamed and OS (oversize) guides installed.
Guides may appear "tight" to you, but as soon as the head is warm they are loose.
Sitting down flush like that is not normal.