I was taught from a very young age by my father "the coolant and the air are free, make sure both are flowing freely"

As long as your current cap is sealing and holding a few psi of pressure I can't see what your going to gain by changing the cap other than a very small amount of temperature increase before boiling point reached

I would suggest you either have insufficient coolant causing an overheat issue, flow of water, and air through core needs checking, or you have combustion pressureizing the coolant.

I've had this several times on machines and it only takes a few flutes to be blocked in the radiator to cause issues, light load scenarios will be fine but full load flat out temps quickly rise and will boil and blow water out

Obviously check thermostat is fully opening as well