I think it's the carb, Too mush fuel Options

[porschetub]

It’s been 5 years. But I finally got to drop the engine and remove the head.

Pretty ugly.

Repairable, or should I be looking for some new heads?

What causes this? Want to make sure it doesn’t happen again.

Thanks

Overheated engine,tight exhaust valve clearances,lean carb setting or lean FI,or timing wrong and a few others, surprized the valve seats didn't come loose...dodged a bullet there,lucky guy.
The heat gaskets don't look great and have been leaking.
Find a good used head...only solution but you need to find what caused it from the start,good luck.

[Superhawk996]

Not really repairable.

Well . . . everything is repairable given lots of time and money.

Since heads are still readily available, you'll want to simply replace. There is no point in trying to repair these. These are very far gone and aren't worth repairing. HAM has new heads available.

As to cause. . . In my opinion it looks like damage from running lean and overheating and has eroded the head around the valve seat. Potentially had some detonation going on too to have caused that kind of massive errosion of the aluminum between the valves.

At this point, you need to take a very close look at your pistons and rings too. I'd be surprised if they were not in bad shape too given how bad these heads look. If there was detonation going on, it will have taken a toll on pistons, rings, and wrist pins. All of those can be inspected without splitting the case.