Hmmm, if it is a braking problem I doubt that more rear braking will solve this problem because of the weight distribution and FWD braking bias Less front braking would reduce the effect but you need awesome
I know how you feel, I have a mate that has just completed an LS1 S14 build which is farking awesome. It's just as fast as my car, sounds awesome, is clean and reliable but at the end of the day I still love jumping in the GTR and hearing it scream.