Remember, the Manoeuvering Stall Speed is proportional to the square root of the G, times the 1G clean stall speed.
eg at 4G, your new stall speed is doubled (2 being the square root of 4G)
and at 9G, your new stall speed is tripled (3 being the square root of 9G).
So at 6G (if that is a Cessna Aerobat limit), the Vman = 2.449 x Vbs
(2.449 being the square root of 6G, and Vbs being Basic Stall Speed).
If your Basic Stall Speed is higher, due to heavier Mass, then your manoeuvre speed also increases.
If you are flying slower than your Man Speed, you cannot pull 6G before you stall.
If you are flying faster than your Man Speed, you can overstress the airframe.
PS. Keep in mind the Rolling G-limits, and the effects of rolling with aileron PLUS pulling G. You can easily overstress just the one wing....