Chi Chi was stronger than Chapa-o (23rd Budokai), who was already considerably stronger than the Goku who beat him in the last tournament, who was stronger than 22nd Budokai Chapa-o, which strength was already greater than that of post-Karin training Goku.
Chi Chi >> Chapa-o >> Goku (22nd Budokai/suppressed) >> Chapa-o (22nd Budokai) > Goku (Uranai Baba)
^This is at the very least. Based on Chi-Chi making Goku weighted (although heavily suppressed, at least >>> his 22nd Budokai self, imo) exert a bit of effort, I'd say she was at least at Drum's strength, but probably even higher than that.