Speed Limit on OSM claims it's 70MPH, but according to speed signs, it is 55 MPH. 

However, there is a possibility that it could be accounting for the express lane(s), and I'm not sure if there is a way to differentiate between them.

I tried to edit the speed limit, but I could not using Street Complete EE (SCEE).

via StreetComplete_ee 59.2