I have one RX-7 1993 Twin Turbo 3rd Gen in very good condition.
It's a very nice car but the performance are not as good as I expected, maybe the turbos are tired or something. It has 126 000km with no mechanical problems at all.
I don't really know what a could upgrade to get better performance (new single turbo is quite expensive).
A friend recommended me to get a Turbo Boost Controller, straight-pipe exhaust system, Apex-i Mega P-Flow.
Any ideas?