and the width and height were 5mm less, and the wheelbase remained the same ( 2510mm ). The front track was increased by 5mm, while that at the rear stayed the same. Thus both were now 1470mm. The body was now 45% stronger than that of the standard Lancers, with extensive additional spot welding, and reinforcements around the scuttle, suspension and lower and upper frame; the RS also gained a front lower brace plus additional front cross member. The 4G63 turbo engine was basically the same, although there were many important differences compared to earlier Evolutions.

The compression ratio was lowered slightly from 9.0:1 to 8:8.1, yet power and torque were drastically increased. This was primarily achieved by adopting a new, twin-scroll turbocharger ( TD05HR-16G6-9T ) and a 15% larger capacity intercooler, although there were a number of other modifications too. The cylinder head and lower part of the block were made thinner to reduce weight. The head covered different camshafts ( a red rocker cover became a feature at this time incidentally ), and the lighter pistons. Between the two was a stainless steel instead of carbon headgasket. There was a bigger radiator, a lighter flywheel, straighter intake tracts, and a secondary air injection system on the exhaust manifold to reduce exhaust gas interference and to keep the turbo spinning hard, even at low revs, thereby reducing lag ( this used to be on the rally versions only ). One big bore exhaust pipe exited from the back now, instead of the twin pipes as found on the earlier Evolution models. Power was now quoted at the Japanese limit of 276bhp at 6500rpm, while maximum torque went up to 260lb/ft at 3000rpm. The engine was still transverse, but mounted 180 degrees opposite to that of the Evolution III
which, much to the annoyance of the competition specialists, meant accommodating a larger transfer box - it was bigger, heavier and more expensive
to produce. A new W5M51 gearbox with shorter shift strokes was employed, coming with revised ratios ( still close ), plus the option of a "low" and "high" final drive on the RS. The GSR was listed with 2.785 on first, 1.950 on second, 1.407 on third, 1.031 on fourth and 0.761 on top, while RS had the same bottom two ratios, but a closer 1.444 on third, 1.096 on fourth and 0.825 on fifth. The final-drive was 4.529:1 on the GSR and RS "high" option or 4.875 on the RS's "low" specification. A new feature was the AYC ( active yaw control system ) rear differential, which used electronics to hydraulically give more torque to the outside wheels, and less to the inside one to improve cornering. The GSR came with AYC at the rear, a viscous-coupled centre differential with a 50/50 split, and a helical front LSD; the RS's rear LSD was a 1.5 way mechanical type, while the torque-sensing helical front was listed as an option. There was a multi-link rear suspension, and a revised geometry up front to give a lower roll centre; anti-roll bar diameters were 23mm up front and 21mm at the back. Brake feel was enhanced through the use of bigger ventilated discs on the GSR - 294mm at the rear – made possible by the move to 6.5Jx16 OZ 12 spoke alloys with 205/50/VR16 tyres. Interestingly, the rear discs incorporated a small drum for a more efficient handbrake. ABS was standard, although the RS - still built to order - ran on 6.5Jx15 steel rims shod with HR-rated rubber, and had the small diameter brakes carried over from the Evo III; the 16" wheel and tyre combination was an option on the RS. In fact, there were five RS set packages; AYC, 16" wheels and tyres, bigger brakes, a front helical LSD, and a close-ratio gearbox with a "high" final drive for circuit use. Inside, the front seats were full Recaro buckets, trimmed in a buckskin-type material. There was a similar but new Momo steering wheel and a leather gearknob. Dual airbags came as part of the GSR package, but not on the RS, as this had a different steering wheel. White-faced gauges were adopted at this point, with an LCD trip and odometer. Equipment levels were basically the same, with several detail differences. There was a green tint on the glass, and the 6- speaker stereo went into the options list. Heated door mirrors were also listed as an option, and a Ralliart sports kit was available from September. The GSR was listed at 2,998,000 Yen. Production planners called for 6000 to be built, including the basic RS, which was 500,000 Yen cheaper. Of these, a total of 107 were exported officially. Excellent press coverage helped sales and the first 6000 machines went quickly [in just three days in fact], so another 3000 were built in September. Ultimately the ratio was about 90% GSR and 10% RS. With Mitsubishi UK hoping to sell the model, a few made their way to the UK. One such car [P66 MRE], was tested by Complete Car in its May 1997 issue. It stated: "Almost certainly the most refined  and usable homologation special ever made, the Evolution IV perhaps lacks the extrovert buzz suggested by its appearance, but there's no doubting its massive dynamic and performance capabilities".