So, in 2014 my best time was 1:12.73 with following specs:
1997 Impreza STi Typre-R, Version 4
EJ20K engine, VF22 Turbo, stock STi Yellow injectors (I believe 440s), ESL-upgraded ECU running @1 bar boost
Stock V4 intercooler, stock full intake incl air box with air filter
Magnecor competition 8.5 mm spark plug wires
Redline 10W-40 fully synthetic oil
Unknown stainless steel exhaust manifold, 4-in-1 design, 3-inch turbo-back custom exhaust with 200 cpi sports cat
Whiteline roll center andjustment kit
Whiteline front 22mm and 24 mm rear sway bars set to max soft*
BC coilovers Type MH inverted type, pillowbal adjustible top mounts F and R, 5/4 kg/mm springs
Hardrace rear trailing arms and adjustible track arms (more camber adjustment) with hardened rubber.
ALL other rubber parts in suspension and engine/transmission mounting are replaced with STi Group N parts.
Coilovers set almost to max hard setup 27/30 - F and 25/30 R.*
Camber -2.0 F and -2.5 R
Stock GC8 STi brake setup with 4-pot front and 2-pot rear calipers, vented front and rear discs, EBC yellow stuff pads all around and new unbranded "performance" grooved brake discs
walbro 255 lph fuel pump with wrong in-tank fuel filter causing starvation in right turns with less than 3/4 fuel in tank and super-cool custom anti-surge tank which made problem even worse...**
Advan RG-like replica wheels (9kg) with Dunlop Direzza DZ03G (H1 compound) in stock size 215/45 R17. Slightly rubs inner fender in front due to less ride height .
Exterior - original V4 Type-R exterior, except for e-bay fiberglass JUN-replica front lip.
Stock STi V4 5-speed transmission with DCCD
Stock diff (R180) with LSD overhauled using original STi LSD overhaul kit*
Motul transmission oils where applicable
MapDCCD controller adding automatic center diff mode - great tool, really allows you to use AWD on GC8
RaceDAC data aquisition system allowing to record 8 analogue data channels and 2 digital channels, with built-in 3-axis G-sensor and supported by RaceChrono - great tool to measure and improve your performance.
VDO oil temp and oil pressure gauges mounted in original gauge pod
fuel pressure sensor connected to oil pressure gauge trough 2-way switch, also logged by RaceDAC.
All the rest is stock.