I am sorting out a 12 sec R33 gtst setup. I am running a GCG stage 1 highflow @16-18psi, power fc etc,etc. My question is how many people have tried aftermarket cams, such as HKS or Tomei and the like. What sort of perfromance gains did they net?? and are they believed to be necessary running the above boost?? What setups are people usung to put down consistant 12 sec 1/4 miles.