Air compressor head bolts

["Larry list account" <list@marketvalue.net>]

I had to replace the head gasket on my air compressor.  The head is
aluminum, as is the block.  The bolts are graded bolts.  They appear to be
grade 5 (three radiating marks and one triangle).  

Here's the questions.

Any idea on the torque spec?

How about washers for the bolts.  Seems that tightening the bolts against
the aluminum head without washers is wrong?  Thoughts?

Thanks in advance,

Larry Hoy