ok i'll go through the mistake I made, i put an o ring that came in the gasket set on the end of the spray bar that joins to the oil pump as indicated in the engine section of the cosworth manual (2wd) unfortunately my car is a 4x4 and the o ring should not have been there and caused the pickup pipe not to seal against the pump (the o ring was holding them apart) now if yours is 2wd then it should have this o ring, however your symptoms are exactly the same as mine and I would suspect that air is getting in somwhere between the pickup and where the pickup joins the pump, or perhaps the pump cover itself.