[panick21_]

That was also a thing yes.

You can look various talks and papers from back then. NASA made a lot of 'studies' back then. One of the SLS engineers in a talk basically said 'I can not do another vehicle study, I have done to many'.

They were evaluating a RP1 based first stage with a large gas-generator kerlox engine. In these studies they often don't use engine names directly. That of course is F-1, see F-1B on wikipedia to get some links.

Somewhere I have some reddit post that have 100s of links to all the different studies and videos on this topic. I can check tomorrow if I can find those posts.

A modern J-2 and F-1 would basically make a modern Saturn V.

Of course from my perspective all these studies are not gone have the right outcome because they aren't actually asking the right question in the first place, but that's another matter. But the results of the study didn't actually matter because congress basically mostly just decides it anyway.