skidmarkSS

iTrader: (3)

I am ordering a Moser 9in.for the Monte SS in my sig,the car has worthless drum brakes in back,my new rear is coming with LS1 flanges because i have extra F Body calipers and all that.My question is,will i need to upgrade the master cylinder and proportioning valve to OEM standards or will i have to go with a more radical expensive set up for extra braking power going to 4 discs instead of 2 discs in the front and drums in the rear?