Upgrading brakes on my gt 150

[bazz33]

I’ve had my GT 150 since new 2008 but have always felt the brakes under perform for the power the car, I’ve tried drilled and vented discs in the past but they still don’t fill me with confidence when they are needed. Does anyone know if it’s possible to fit discs and callipers say from a RS or a 225 ?
Baz