A 7# cap raises the boiling point of the coolant to 233 degrees at sea level. If you're hearing gurgling in the system, that means at least some places inside the water jacket are getting a lot hotter than the laser is showing. Since the temp inside the cylinders approaches 2,000 degrees under load, that's not surprising. Just put a puke tank on the system, and stop obsessing about it. A dangerous overheat situation will result in a boil-over, not a little dribble of coolant.
Jerry
