You could overclock your webcam
Seriously, your upload will be MUCH slower than your download speed. Do a
www.dslreports.com speed test and see what I mean.
You cannot make it go any faster than your internet connection will allow, and this is always affected by internet congestion and the other end of your video conversation affects this too. The other end's upload speed is in effect how fast you will see it on your end. If that person's upload is slow, your download will not in effect be any faster than their upload. Sure, you can get 3000Kbs, but that doesn't matter when the other end cannot send it any faster than 700Kbs.