Is this correct?

Question

そうだったのオレはてっきり

Translation: I was right, there's no mistaking it

this is pretty difficult to translate without context but your version sounds wrong. — Igor Skochinsky, Jun 22 '17 at 16:01

Yuuichi Tam · Answer 1 · 2017-06-22T19:08:47.280

2

そうだったの means "Is that so!", "Now I understand". This phrase ～だと思った probably would follow after オレはてっきり. So it means "I certainly thought that ～".

edited Jun 22 '17 at 19:08

answered Jun 22 '17 at 16:37

Yuuichi Tam

この「そうだったの」は多分 "Is that so?" の方が自然だと思います。「発見の"た"」というそうです。 – naruto Jun 22 '17 at 18:35

1 Answers1