I know a while back there was talk about WRX rotors then it was brought up again recently , but nothing ever come of it that I know of..
The hat depth seems to be close to that of a c4 vette around 2.2" on them .. The BRZ is 11.5" roughly and the wrx you can for $$$ get the 13" upgrade.
The 13" vette and 12" vette swap is pretty inexpensive... I'm sticking with the vette and camaro caliper swap , but would like to see someone do something new..
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87 GT
series 1 3800sc (7.597 @88.53 1.579 60ft)
(series II swap in progress)
85GT Northstar
86GT 3800 n/a