wondering about cam and torque converter combo

If you install a smaller cam it will make more low end torque which will cause the converter to stall a little higher. Probably won't be a huge difference unless you go way down on the cam.

If you want to keep it streetable (3.91~4.10 gears are neat for power but terrible on the hwy) and want more torque without giving up any top end hp switch to an aggressively ground solid lifter cam. Doesn't have to be any bigger than what your running now, just aggressive lobes (meaning they pop open and closed real fast). Go with a tight lash cam and you won't even have to adjust it all that often. Usually once a year depending on how much you drive it. I'm running a Racer Brown ST-14 and love it. It'd work real good in your combo too