I am about to give my new to me procharged 502 an oil and plug change. Just wondering what the best oil and plugs recommend in the powerboating scene is.

A good synthic oil such as Mobile 1 10w30.I use that oil in my 502mpi Scarab scs and my high reving race car.

In regards to plugs not sure with a procharger.With my race car with nitrous I run a very cold plug.

Do a search here on "Marine Lubrication" and you'll find the holy grail of all things oil related. Good luck!

Having used almost all plugs, I have resigned myself to believing nothing holds a candle to NGK. They just do not have failures like many of the others

10W-30 is too light for a 502.



NGK's give the smootest idle in a 502..

Really.Maybe I'm doing something wrong.For my altitude which is 6k feet 10w30 I thought was a good weight oil.Perhaps you can advise me as well whats a good weight oil.

Any plug except Champions. I had one blow the electrode completely out. I thought I had puked an engine.

20-50 Pensoil or Kendells

I would think that boating down south in warm water you would want to use a straight weight oil, if you run conventional oil. Not many syntetics are available in a straight weight so I would use a multi grade then. I use Amsoil Diesel and Marine.
I've been told NGK plugs are the best.

with out question, Mobil 1 15w 50 synthetic for all marine application engines. and NGK for the spark plugs, v-plus if you can for the cgarger app.