2.76 open to 3.55 Sure Grip...expectations too high?

I swapped cam, went from 2v to 4v carb, and HE268 cam and headers on my 318. After the engine mods I still had the 2:76 7 3/4 in it and it was still a dog until it got up into the power band of the cam. I built an 8 3/4 with 3:55's and the difference is night and day, all I can say is the grunt factor is way more than what it was. I too have not changed the converter, when I do I suspect it will be even more noticeable from a standstill.