RikudoSasuke wrote: i believe he did say WITHOUT KURAMA.
Considering his Ashura Sage Body and Uzumaki heritage, his base healing must be pretty damn good. Kurama made it better, but it's not clear just how much. At gaiden he got a sword through his chest and it didn't seem to stop it. That seems to be better than we've seen so far.
However, Naruto has been jinchuriki since birth, and Hashirama never was one. it's fairly difficult to tell just how strong Kurama's healing was.
In the "Boruto: Naruto the Movie", Naruto uses Kurama's chakra for heal Sasuke's burns, in few seconds.