Brake master cylinder sizes

[bam914]

So I ran my first event in my Boxster last weekend. It rained on Saturday so not much dry track time. On Sunday I finally got a dry track. Everything went good. But there is one issue I might not be able to over come and this is going to sound crazy. The brakes work to good. I can't run the ABS in the class I run in SCCA. So braking is extremely hard to do without locking the brakes up. I am running Hawk DTC 70's in the front and HT-14's in the rear. I am use to having crappy brakes from when I raced Honda's and 914's. I really need a hard pedal that takes a fair amount of force to slow the car down. This fits my driving style. Now I am having to brake for a much longer time then I like to. I have read about guys swapping to a larger master cylinder on their 996's. I tried finding a list of sizes but came up short. Does anyone know of a large MC to make the pedal harder or have a better idea?