Hi Guys, i have a stock 2002 Corvette LS1 in my ski boat with 460 hours - It's a beast. Since break in it's been ran with M1 15w50. I purchased the boat this spring and left the 15w50 in it since it was fresh, but felt it might be a little too thick of oil to run.
When i changed it this fall, I put in 15w40 dino (per the boat manual) . I actually noticed a slight improvement in acceleration - not sure if it was just in my head. There was no change in oil pressure going from the 15w50 to the 15w40. 35 PSI idle, 50 cruising and 60 wide open.
Anyhow, GM normally specs M1 5w30 for this engine in a car. I know the arguments for thicker oil in a boat due to higher RPM and loads on a boat and higher shear scenarios. But is that old school thinking ? I have read other views that i should be running thinner oil. Some of the newer boat engines are actually running this grade.
Probably just over thinking this but I plan to keep this boat for another 20 years. Thoughts ?
When i changed it this fall, I put in 15w40 dino (per the boat manual) . I actually noticed a slight improvement in acceleration - not sure if it was just in my head. There was no change in oil pressure going from the 15w50 to the 15w40. 35 PSI idle, 50 cruising and 60 wide open.
Anyhow, GM normally specs M1 5w30 for this engine in a car. I know the arguments for thicker oil in a boat due to higher RPM and loads on a boat and higher shear scenarios. But is that old school thinking ? I have read other views that i should be running thinner oil. Some of the newer boat engines are actually running this grade.
Probably just over thinking this but I plan to keep this boat for another 20 years. Thoughts ?