A buddy of mine bent a valve, we pulled the head and had another head laying around, so we pulled that valve out and put it in the original head, in the process we changed the timing belt and balance shaft belt, well we get everything back together, the valve is seating correctly, and it's dying out around 4500-5000 rpms, and has a slight miss to it, the intake is sucking VERY loud, much louder than it ever has.. any ideas?