Could it be a belt slipping at high RPM's?

I would say it's your internal flappers burning away. They don't last very long

I found a couple of things lying on the #1 exhaust manifold runner where it attaches to the head. I found 2 little rubber tips (partially melted) that must have fallen off some hose clamps and a round cardboard type of material you would find in the underside of a cap on a quart of oil. The round cardboard thing was charred/black burnt. So I'm hoping these things were contributing to the smell. I'll be taking it out tonight.

Instead of trusting that the raw water pump was replaced and flushed properly why not spend $100 and replace/flush yourself. If original impeller is good keep it as a spare.

Said it was used condom melted on the exhaust riser.

Am I the only one that doesn't think you should find anything charred or burned looking on a properly cooling motor?

Details.........

I was thinking the same thing.

I found a couple of things lying on the #1 exhaust manifold runner where it attaches to the head. That was quote from FBRONCO. If you can squeeze a finger down there on your motor ,Hold on to it and report back how hot it is..........Kidding

Those blacks cap on the end of hose clamps fall off all the time. Lay one deep in between the spark plug and the cylinder head. Let me know what happens over time. Just saying