"So called blown motor"More info needed. What is it's history?
Oiled up top end:
Could be shot oil rings, but a compression test could have shown this before the head was pulled.
A lot of oil in the intake manifold could indicate badly worn intake valve stem seals.
The oil is sucked out of the valve top chamber and into the intake.
Disassemble a couple of intake valves to check. Seals may be cracked and hard. Check the guides also.
Running in:
Overkill maybe, but I ran in my new reco 3SGE with 3 lots of Penrite running in oil (mineral)
Changed at 100kms, 700kms and then went to full synthetic after a two thousand kms.
Manual says use a 10W-40 oil.