NO, NO, NO, A pressure REGULATOR CANNOT INCREASE pressure IT REGULATES the INCOMING pressure to working pressure and keeps pressures UNIFORM ..A regulator NORMALLY REDUCES pressure to safe levels STEAM from 125# to 10 PSI water to a safe level for the piping about 40-85 PSI depending on size (DIAMETER)
THINK of an OXYGEN Tank with 3,000 PSI with a regulator WHY WOULD anyone in their RIGHT MIND want to increase this kind of pressure and HOW can you increase in coming pressure from the street other then some type of PUMP (BOOSTER)
To find out if your main is indeed leaking SHUT your main VALVE listen to the darn pipe for the sound of running water. IF you hear the sound of running water CALL A Licensed plumber