Setups vary depending on goal. You can be as ambitious as you like, the $$$ is the limit.
Originally,
I went with a RB30NA engine
installed Turbo (GT3540),
chinese stainless crap exhaust manifold,
intercooler,
custom made intake manifold,
reprogrammed the standard ecu,
installed a tailshaft loop,
thicker head gasket,
surge tank,
higher volume fuel pumps,
1500cc bosch injectors
Mass Air Flow meter from a USA ford truck,
Trimatic 3-speed w/3000 dominator stall conv,
eboost2 boost controller,
billet axles,
3" full ex system.
Car ran 12.1's @ 122MPH on 26psi at WSID with no more potential left in it.
Then after some dissatisfaction,
Billet crank,
N1 Oil pump w/billet gears,
H-beam 4340 rods,
ARP everything,
CP forged pistons,
custom RDG engineering modified Oil Pan,
big camtech sticks,
RB26head that I spent a month prepping,
RB20DET ECU that I reprogrammed,
big PT6466 precision turbo (that you can't buy parts for, stick with garrett),
6-boost exhaust manifold (that welds fell off in the first 50Kms of heat/pressure and destroyed Turbo ex wheel)
Cometic gasket kit,
oil catch can,
breather kit,
some LS2 coils and wired in to a RB26GTR Loom,
3.5" dump pipe, blended in to the 3" cat back.
The goals change as time goes on but it all started with a bet that an engine I built couldn't beat the old one.
Well it did on the first pass at WSID last week.
the car ran a 12.0 @ 124.89MPH on street 225x60x15's but it was a handful with only 16psi. Way too much potential left in it.