It's quite sad to think that the current generation of the Lancer Evolution will be the final one for quite some time. Mitsubishi's recent move to dedicate all their efforts towards the development of electric cars has left the Evo without much of a future. We do hope however that MMC will continue to produce the CZ4A for at least a few more years as it continues to be a key car in the tuning world. We recently took a look at the Koyama Racing Labo Evo, an outstanding machine, testament to the impressive work God Hand Koyama is known for.
If you have been keeping up with the various time attack coverage from Japan like the Tsukuba Lap Battle and the Option Speed Max in Fuji you may recall seeing the Varis Evo X, which remains the fastest new-gen Evo around Tsukuba circuit with a 57"963 lap.
The car is a collaboration of three very well known and respected names in Japan: Varis, which specializes in the design and production of bespoke aero parts, Garage G-Force, a top player in the engine tuning side of things and Sunbeam, a suspension and brakes specialist with years of experience in setting up a vast variety of cars. With a trio like this coming together it was obvious the resulting project would be of the highest standards.
The goal was a simple one, to create the fastest Evo X, something the car achieved pretty much straight out of the box, recording its fastest lap back in December 2009 at the Rev Speed Lap Battle. Varis developed a special lightweight series of carbon body parts to help not only give a more purposeful look to the exterior but also generate higher levels of front and rear downforce.
When running highly tuned engines cooling becomes an extremely important aspect of the whole package and once Varis knew the precise dimensions of the HKS R-type intercooler, designed a complex center section that not only keeps the core constantly cooled but also directs air towards the front brakes. In the above image you can also see the airbox scoop on the right side of the grille that helps achieve a ram-air effect once the car is traveling at speed.
The carbon hood helps lower engine bay temperatures as well as supply much needed cool air to the rear side of the engine, where the turbine is located.
Garage G-Force rebuilt the all-aluminum 4B11, fitting Tomei 87 mm forged pistons, Cosworth connecting rods and a Cosworth billet crankshaft that increases stroke to 94 mm, bringing capacity up to 2,234 cc. Special G-Force camshafts, 264º on the intake and 260º on the exhaust side, were dropped into the specially ported and polished head. HKS supplied the GT3240 turbine and external wastegate, which barely fits between the engine and the firewall. The blower is force fed cool air straight from the grille thanks to the Colt Speed carbon air box. Fuel is supplied by the four 1000 cc/min Sard injectors and managed by the special G-Force ECU. The engine cranks out a respectable 570 HP and a very usable square torque curve peaking at 477 lb/ft.
A closer look at the G-Force 90 mm straight through titanium exhaust and Varis carbon rear diffuser.
Sunbeam took care of custom valving a set of Spirit Racing adjustable dampers and then matching KYB springs, 20 kg/mm for the front 18 kg/mm at the rear for a true time attack set-up! Suspension modifications include stiffer Ralliart bushes and larger diameter Cusco stabilizers. Sunbeam knew that at this level no chances were worth taking so went with the best brakes currently available from a Japanese maker; Endless monobloc 6-pot front and 4-pot rear calipers mated to "E-grooved" 2-piece floating discs, 370 mm at the front and 332 mm at the rear were chosen for this application. Race-spec Endless N84M brake pads are employed all round.
Weight was eliminated at the rear thanks to the Varis carbon trunk, on top of which is fitted the obligatory GT-wing.
Carbon front and rear doors are without a doubt the parts that help shave the most weight off the somewhat portly Evo X RS base car and are even fitted with lexan glass at the front…
…while the rears do without glass all together. Here you can get a good look at the chunky carbon fiber strands that Varis often uses on its products.
More carbon fiber in the complex side skirts, again designed to benefit airflow by stopping air moving under the car and creating unwanted lift.
The interior is mostly stripped out and fitted with a chassis-stiffening Cusco roll-cage and a pair of Recaro bucket seats. The stock instrumentation remains, but is joined by a more accurate Racepack IQ3 data logger and dash unit.
The Evo X has come a very long way since its initial launch back in 2007 and cars like this example tuned by Varis, G-Force and Sunbeam prove that there is far more potential in the CZ4A to succeed in the highly competitive time attack scene. Only time will tell if tuners will manage to make the Evo X even quicker, before MMC goes all-electric!
-Dino Dalle Carbonare