If you go to a thicker oil wont you loose the 1-2 hp you just gained by using synthetic? Also I have a friend thats a certified honda mechanic and he told me that on a higher mileage engine there is scars in the cylinder walls most likely and using regular oil will cover them so you have "normal" compression i guess you could say. He said if you use synthetic it will clean that "crap" out and the scars will let your mixture go by the rings and therefore loose compression. So is that right?