The oil system is far more important than what oil brand and weight you are running. If the system isn't right you can use $15/qt oil and the motor will blow up. If the system is right you can run $2/qt oil and it will not blow up. I run wide open for long periods of time and I always have 60lbs with 30wt oil. The motor is spinning almost 7000 rpm. NASCAR runs 0w5 weight and run wide open alot longer with alot more rpm than a boat. So, if your having oil pressure issues changing weight, brand ect. Is not going to fix the problem.

Your oil temp is probably your problem but you should cut open an oil filter to make sure it is clean. After that try to get the oil to run around 190-200f cruise and not go over 230f after wot runs. Get a cooler with a built in tstat as well or you will be fighting oil too cold issues next. Hardin makes a nice one I believe that works well. As far as the original question on how long at wot, I ran my junk in rock the bay poker run at wot throttle for what seemed like 15mins at least. Gopro review showed just over 1 minute which seemed like a long asssed time. So unless people are measuring the time at wot, I'd guess most are big fish stories )

Thank you Black Baja and Blue Thunder, u don't know how much I appreciate your input. It is very clear to me now what is important about the oil system. So does the oil temp gauge mount on the oil cooler? If not where can I install the OT? I This will be my priority project. I will call Hardin Marine on Monday. Getting a OC with a Tstat makes real sense. Again thanks guys. Gary

My oil temp sender is in the remote oil filter pad. The oil feeds directly out of the pan to this point in my system so it is pretty accurate to what is happening.

Yep I see the spot where I can install OT sender!