I am new to boats and really don't know a whole lot. I bought a jet boat with a 454. I just had the oil changed as well as replaced the header gaskets due to an exhaust leak. I took the boat out today and noticed white smoke coming from only the right header. The other header did not smoke once, as if it wasn't running. As I idled out my oil pressure was at 60. Once I started getting on it, I heard a ticking as if there was still an exhaust leak. There was still white smoke coming from only the right header. As I turned around to head back I could hear a slight whistle when letting off the throttle. I noticed my oil pressure was down to 15 once the motor was hot and I idled back.

I am wondering if those are normal oil pressure numbers. Can an exhaust leak cause low oil pressure? And why is only one header smoking and not the other? Thanks in advance.