Sounds like you have a valve lifter dogbone failure causing the lifter to rotate in the bore destroying the lifter causing it to stick in the bore. Hence valve to piston contact bending the pushrods. It will cost you a camshaft and lifters plus possible machining of the lifter bore. Place 2 dogbones on each lifter set to prevent it again. This is a common failure on these engines that should have been fixed years ago. Could be worst you could own a fisherprice 13 liter.
