This saga is hard to figure. The overall chain is Goku >= Tenshinhan > Muten Roshi > Tsuru > Kuririn >= Yamcha >= Chaozu > King Chappa > Panputto. That is without doing the complete breakdown.
Talking about Tenshinhan, I think he displayed 7 different levels of effort:
1- His initial power to fight with the guys in the preliminaries. Yamcha and Kuririn were a bit surprised, but Kuririn even said it's not that of a big deal:
Kuririn - He wasn't all that amazing.
2- When he fought on par with base Yamcha and all were like "Whoa"!! This power is equal to base Yamcha:
^This power is probably on par with the power Goku used to defeat King Chappa or stronger (see SIAD's points).
3- The power he used to match Yamcha's Fist of the Wolf Fang Gale 2.0, actually having an advantage in the ened:
4- power used to block the Kamehameha. I actually think he powered up to do this, since the Kamehameha was Yamcha's special technique.
This power could also one-shot Yamcha and was the same he used initially against Jackie Chun IMO.
5- When Jackie Chun got serious Tenshinhan did the same, even more considering they were basically equal before. If Jackie Chun used more effort, then Tenshinhan had to do the same in order to fight evenly with him. Also, look at Jackie Chun's face when Tenshinhan was coming at him:
Clearly a difference in effort.
6- The power he used to get the advantage over full match level Goku, who is a little bit stronger than Kame-Sen'nin unseen full power IMO.
7- His full power, used right after Goku showed his battle level.
I only have a bit of trouble figuring out this quote, used right after both Tenshinhan and Kame-Sen'nin got serious:
Chapter: 124, P2.1-2
Tenshinhan: “Alright, I’ll fight you seriously just a little bit…!”
Kame-sennin: “Wha!? Are you saying you weren’t [fighting] seriously before?”