Hello, have gone for 32lb\ft with no problems, suppose this equals "really tight", tightening in the correct sequence, fingertight first then max 5 lb\ft at the time. Retighten is good after "some" miles to compensate for compression of the copper gasket. No idea of my bolts' tpi. Some info here
http://www.audioworld.net/BSA/head.htm Hope this helps
Regards
Erling
A10gf 53