SsjB goku-initial merged Zamasu Gap

[KyuubiAhri]

In the manga how big was it?

 

[Captain Cadaver]

Really depends on how the manga portrays Goku in comparison to the Hakaishin in the manga. Anime-wise you have Champa being somewhat shocked by SSB Goku's power during the baseball episode and even hyping him up as a fighter without limits during the Exhibition Match, as well as Sidra being in complete awe at his power before the Kaioken stacking. If the manga keeps anything similar, any more than a 2x gap seems doubtful. The feats Zamasu presented aren't anything such a gap couldn't cover anyway.