it takes the roto-start system off of the k4.6 engine, i am betting you have the .25 motor in your savage, so you will have to buy a different rotostart backplate either way. Dont worry about changing the cooling head, the one on that motor is better than any aftermarket one plus chances are like i said you probably have the .25 motor so there is no way your cooling head would fit on a .28 motor.