Answer:
I honestly don't know if you're being serious or not as this was a popular thing a few years ago, there are a few videos on yt, one particularly from 2008 that answers your question pretty well.
Clipping through a loading area requires at least 400 speed. But if you're just interested in the usual speed, there are multiple glitches to make him go faster than his usual x3.5 increased running speed (which is the speed you get at the LEAST when BLJing) but it seems the average is -200. I've seen people get up to -900 though, so.
Basically, it can vary. In a very specific area he can get max momentum of -9373, which is probably the fastest even though it's against a wall.
Unicode is a 16 bit system which can support 65636 different characters which is much more than the number of characters that ASCII code support.
