Best Answer Paul_S , 24 July 2018 - 08:20 PM
I can see why they said it was the head gasket because that's a classic sign. The cooling system can be over-pressurised by the combustion process when the head gasket fails.
But, that said, I've never heard of this happening to a 350Z or 370Z. I think Greg has more than likely given you the answerGo to the full post