Since we’ve eliminated every component of the valve train, the only other place the noise could be coming from is the bottom end of the engine. We know the top of the piston in cylinder #6 was heavily damaged by the nut, and it’s possible that it broke a ring or damaged the area around the wrist pin from the excessive forces of hitting TDC with a nut trapped in the cylinder’s squish area.
We called Ford Racing about this to get the part numbers for the damaged piston and ring set. They needed to have someone from another department look that up and told us they’d get back to us. Today, we got a shipping notice from Ford saying the parts will be here next week! No charge, apparently!
We need to pull the oil pan to remove the piston, and we can’t pull the oil pan with the chassis sitting on the car dolly, so we’re going to move the car over to the lift this weekend so that we can easily access the underside and drop the pan.