You will find it much easier to make your loops round by cutting power on the down side of a loop....a loop is round not oval or egg shapped....you want to exit a loop at the same altitude as you entered....so cutting power on the down side you don't have the engine trying to flatten out the back of the loop....also if you watch someones thumbs while they're doing a loop they don't just throw in elevator...but at the top of the loop may be giving down elevator