Bad Advice !
Just tore down a 2005 280 with 80 hours showing on the DDT and to my amazment the bores were cut to pieces above the exhause port. The top rings were stripped of all the TiN coating and the ring edge was sharp enough to shave.. I quized the owner what type of oil he was using and he told me the brand and that the dealer /Drag boat racer he bought the motor from NEW told him to mix 2 OZ to a gallon instead of the ROS ECU equiped factory required 4 OZ to a gallon.. VERY expensive lesson, when in doubt the factory suggestions would be my suggested ratio on pre mix ratios...
Jay @ JSRE