Actually, you should be trying to minimize the pressure needed to stop your notes and not increase it. When I played back in the old days I hand an "Iron Monkey Kung Fu" grip. The more challenging the passage the more pressure I'd use, like an idiot.
Today my fingers float over the frets. My touch is so light, I seem to barely have enough pressure to fret the friggin notes. It works out well. My speed has increased and I seem to be requiring fewer tries to work out difficult passages. Now it all makes sense. How can you expect to gain any speed when all of your muscles are constricted? Freedom of motion requires relaxation rather than more tension.