Head torques and radiator pressure

[aroostok]

Was reading an article in a recent "Classic Motorsports" (July 2008, p.133 ff) on a power increase on a MGB-GT. Sort of fascinating article in which something struck me. When they had removed the head and replaced it they torqued the head bolts to 55 ft.lbs. Is the recommended value? I remember when I took the head off my B recently to have the head checked for warping and magnafluxed that the highest torque that had been used was 45 ft.lbs. on any of the nuts. Could this have been a part of an overheating problem I was having that caused me to take the head off in the first place?
I have a new Payen head gasket I'm going to be using when the head goes back on.
One other question, this is a 76B converted to dual carbs. I have a new radiator in it with a 13 lb. cap. Is this the right pressure cap I should be using or should I go lower?
Thanks all.

 

[DrEntropy]

Recommended torque is 45~50 lb/ft., I usually go the 50, in the workshop recommended sequence. First to 25~30, then to 50.

Unless there's some OTHER problem (head warp, the #3 infamous crack) that should be enough. Going to 55 can strip those fine threads off'n th' studs, 'specially if the studs/nuts are reused.