you should probably do a search, there's lots of information about this topic already, although it's probably spread out over various threads.
To summarise, I'll start by going over the JDM VR-4s - I wouldn't really have much of a clue what the USDM/AU VR-4 has or what it doesn't have.
The JDM VR-4 was first released in September 1987 with two models, the VR-4 and the VR-4 RS.
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Both had the 205PS engine with 450cc injectors, TD05H-14b turbo, 3 bolt rear end with the RS having a plate type LSD. These had the KM225 gearbox of which some or all of them had the 2WD bolt which would convert it to FWD if the rear driveline was damaged for some reason (probably just used for rallying). Both ran 3.545 diff ratios. Inlet manifolds were the dual runner type with 'CYCLONE' and 'TURBO INTERCOOLER' writing. Brakes were the smaller 265mm front and rear (front vented). Interior had the twist knob HVAC controls and the dash cluster had the dual colour illumination. Exterior wise the front bumper had the fog lamps with indicators built into them, and dual lamp corner markers.
The standard VR-4 weighed 1340kgs while the RS was 1300kgs.
October 1989 saw the release of the facelift VR-4, of which a new VR-4 called the 'Super VR-4' joined the existing VR-4 and VR-4 RS line up.
Among the facelift changes visually were revised front and rear end with new tail lamps and tail/brake lamps now running across the bootlid, the high stop lamp on the bootlid mounted spoiler was longer and thinner, the front now had dual lamp spotlamps and the indicators were moved to the corner lamps and the park lamps moved to the headlamp housings. New '8 spoke' alloy wheels replaced the original wheels.
Mechanically the engine was still the same with the 450cc injectors and TD05H-14b turbo but the engine was now producing 220PS thanks to an updated ECU (single board as opposed to dual board of the pre-facelift). The facelifted model now used the W5M33 5speed manual transmission, but new was the four speed automatic transmission, of which the automatic models used a TD04H turbo and made 210PS. 3.545 ratio remained for the manual, while 3.307 was used for the automatic. 3 bolt rear end was still in place. The brakes were upgraded to twin piston calipers with 276mm rotors up front.
Interior wise the seats and trim remained the same except for the steering wheel changed to the four spoke design, and the twist knob HVAC controls were replaced with digital push button climate control (of which the RS still uses the twist knob setup). One addition to the interior on the facelift model is the dashboard pop-up box in place of the usual recess where the Active suspension control would be on the 2WD models. Gone was the dual colour gauge cluster illumination, replaced with the standard green across the board.
The 'Super VR-4' had full leather interior above the usual cloth VR-4 interior, and colour coded wheels. As far as I know, the Super VR-4 was only offered in 'Carbon' Black.
The standard VR-4 remained at 1340kgs (1300kgs for the RS), automatic being 1370kgs. The Super VR-4 was 1380kgs with the automatic being 1410kgs.
August 1990 saw new models being released, the VR-4 'Evolution' along with a special limited release 'Monte Carlo' edition to celebrate the VR-4's win in the Monte Carlo Rally. The Evolution was available in 5 speed manual only while the Monte Carlo came both 5 speed manual or four speed automatic.
All 5 speed manual models (including the Monte Carlo and the RS) effectively from now on were 'Evolution' models, while the automatics remained the same as the October 1989 facelift specification.
New with the Evolution spec was the switch to 3.909 ratios, which is the only true way to distinguish an Evolution apart from a non-Evolution model. The notable changes were a switch to 510cc injectors, TD05H-16G turbo, a longer length FMIC with larger diameter intercooler piping, 'ECI-MULTI' and 'TURBO INTERCOOLER' writing on the manifold. This bumped the power up to 240PS while the automatics remained at 210PS.
Manual (Evolution) models received the 4 bolt rear diff while autos retained the 3 bolt diff. The main visual differences for the Evolution models were the addition of bonnet vents and front bumper with extra vents below the main grille. The interior seat stitching pattern changed slightly on the cloth interior models, while the Monte Carlo gained the leather interior from the outgoing Super VR-4.
The now 'standard' VR-4 Evolution 5 speed manual weighed 1350kgs (with RS at 1310kgs), with the automatic at 1380kgs. The Monte Carlo is 1410kgs for the manual and 1430kgs for the automatic, making it the heaviest production JDM VR-4 built.