Does this piston need replaced? (see pic), Dropped exhaust valve from broken spring Options

[dfelz]

Had a valve spring failure on cylinder #2 exhaust, engine was cut very quick after the noise since it was in the garage undergoing tuning when it happened so wasn’t on the road driving, and I’m assuming thank thankfully mitigated worse damage. Just got the engine dropped and the head pulled off for the first look inspection. There are minor scuff marks on the piston head, which could be sanded down and only leave very minor scuff marks remaining is my guess from how it looks and feels right now. But would like the opinion of others if this is the route I should go, or should I just replace all four pistons (since I believe they are only sold in sets)??

As for the valves, should I replace all my exhaust valves anyways while I’m in there? I thought I remembered reading at some point that the exhaust valves have a shorter life since they see more heat. I don’t see any damage to the valve and the valve tube still feels perfectly snug with the valve stem. Any consensus on this front? When I rebuilt the engine 8 years back (was only running for first two now been sitting since then) I can’t remember if the valves were replaced new, I can see from the old pictures the springs clearly weren’t new, hence me now having to deal with the broken one...

Any comments appreciated, thanks

[914Sixer]

Looks good to me, but clean it up to double check

[dfelz]

Looks good to me, but clean it up to double check

Thanks Mark, I'm gonna clean them up this week and have a better look, but glad to hear a first take view that it should be fine!

[type2man]

The valve might be bent, so youll have to check it for leaks once you install the new spring. I would remove the cylinder and make sure the piston rings are not binding. Once the valve smashes the piston, it might cause the rings to bind.

[dfelz]

The valve might be bent, so youll have to check it for leaks once you install the new spring. I would remove the cylinder and make sure the piston rings are not binding. Once the valve smashes the piston, it might cause the rings to bind.

Thanks Type2man. I will be splitting the case to look for any remaining fragments of the valve spring to ensure none make their way to the case, rather be safe than sorry, so will be able to inspect the rings as to make sure they aren't binding. Also ordered all new set of valves since i want sure of the age of the valves anyways, again rather be safe than sorry (again) and figured while im in there ill just do a valve job that i know will hold up for miles to come.