old rings
I think there's a lot of big differences in peoples' opinions of what is "bad", what is "acceptable", and what is "right". I'm too lazy to do it twice. So I wouldn't, even on my own stuff.
Not to mention the combination of boost and worn low-tension oil rings with hyper pistons. You're better leaving it alone. With the amount of blowby, it won't make enough steam to butt the rings. Chances are it will detonate and a piston will crack first if it's pushed to actually try to make power.
All that being said - it's not our car. I'm not going so he's already ahead of me... Go have fun and report back how it does.