Many a debate on what oils to use. Some here use 50wt valvoline, multi viscosity stuff, I run Joe Gibbs Hot Rod oil.
When dealing with multi viscosity oils, engine temps of jet boats (Typically 140 or so degrees) compared to a car (195 or so degrees) this is what they are meant for. Every day all around use, multi viscosity is fine. I don't know where the guy came up with the theory on lighter weights tho.
At temp, the oil is supposed to be the same as 30 weight on your 0-30. at cold, where most engine wear occurs, its at 0? Never seen the stuff, but sounds crazy to me. WTF is Zero weight? Water?
Personally, I would look closely at the Joe Gibbs stuff, expensive, buck 25 a case, but since you have a 540 inch motor, sounds pretty wicked and probably some VERY expensive parts in there. The guys heart was in the right place.
I think Tom at JBP is using something similar from another vendor. Probably the same stuff, really, just a different brand on it.
As far as roost? With the JC you're pretty much at the mercy of the same problem I have with my JE, no split bowl to add droops or wedges, for one. Second thing is the attitude of the boat at speed when the diverter is in full-up mode.
Brad took an awesome picture of my Moo boat at speed and full roost and I realized that while the roost isn't that high, it IS damn long, and the boat seems to have a lot of wetted surface under it considering the up position is forcing it down. More speed is the one answer to my problem to get the ass of the boat out of the water a little more. Working on that, and it's all in the tuning of this thing.
The next steps involve cav Plates/trim tabs, etc to get the attitude of the boat right Mines attitude seems fine, it's a speed issue I beleive.
Post some pics of the boat at speed and full roost, the guys here can tell you what you need to do in a heartbeat!
Ray
