Non resident street parking is more or less impossible to find for
periods of longer than 2 hours. Use one of the car parks that open 24hr
and pay through the nose for the pleasure. Imperial College is one that
springs to mind - approx US$55 per day.

Check that though, with all of the Building work going on, not sure if the
car park is open to the general public at the moment. Might be staff only.

Jaime