Thanks for all your replys. I've decided to go with the Saito 56 for the 4 Star 40 . It will be here Monday. I guess go ahead and run the Cool Power 10% in it that I still have left over. Some of you on another thread said it would be fine. I was alittle concerned that Cool Power is only 17% lube and Saito says to use 20% lube in their engines. Thanks ,JT