UAS spacers are only $350, all you need then is some 324mm RDA rotors or something. That is a brake upgrade for around $500.
You could get away with the standard sized rotors with aggressive pads, but I found it to become annoying after a while and went
with the UAS spacers. I use A1RM as well. Brakes are good, though in saying that, im sure 8 pot ksport would be better
I've only got 210 at the rear wheels. I'm not sure what times youre doing around winton in the s13, but mine does 1.38's with
non r comp tyres (595rs). Still has the interior, sound crap, a/c, heating etc etc. Still looks, kinda (bonnet) like a road car.
Pickup a 33 for 8-9k then mod it as you go...you basically get something like my car for the price of a standard GTR.
In saying that, you could do the same to an s14.