As DXMF said, the relief spring in the
oil pump, which opens a valve to dump excess
oil back into the
oil pan at a PSI determined by the strength of that spring, may for some reason be too strong and not allow that valve to open below 70psi, even in a brand new Mellings (great choice, BTW!).
Perhaps a call to tech support at Mellings could help figure that out and even allow you to get the correct spring to custom set a max psi to suit your engine builder?
Just a thought.
Cheers!
Dugly
