Understand the metelurgical concerns...

I'm not sure the relieving temp- but it has become an industry practice to straighten. Think of a VW head or some other(TR 7) where the camshaft rides in the head. If the headwarps, you loose camshaft brg alignment. I've seen them REALLY BAD (ala TR-7). It was noticable doing a compression test by the un-even sound of the engine.
Just find a good machineshop which does a lot of head repairs.


Michael

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Michael McGuire
83 300d
01 vw A4 TDI
66 Chevy Corsa
68 GMC V6 w/oD
86 300E