If there is a will, there is a way. The Team Takeuchi Lexus IS you see here is quite an interesting car, it was created out of need, and as we will see shares very little with the Lexus IS you and I know. The project was handled by Shift Racing, a highly technological outfit that for years has been building cars that participate in Super GT, Super Taikyu and the Japan Porsche Cup.
With the phasing out of the little MR-S, used by some teams up until 2008, Shift knew that they needed to look to the future with their GT300 project that kicked off back in 2007. The idea came to base the build on the Lexus IS, an unconventional choice for a race car, making it a perfect one to feature for our current Misfits and Mavericks theme.
Super GT regulations are pretty lax compared to a lot of other race series out there. Provided the base car is a production car and the engine is made by the manufacturer teams can play around with lots of configurations, allowing even free choice in positioning and orientation. This is why the engine of the Team Tekeuchi with Shift race car now lies where the rear seats are usually found on a regular IS.
I headed to Fuji Speedway to find out more about this interesting race car, during an open practice session Shift Racing was having.
Like most GT race cars out there, seeing one of these creations up front usually takes your breath away. The almost caricature-like body has been altered to provide as much downforce as possible and wrap around the wheels, now sitting as far out as possible to increase front and rear track, and therefore lateral grip.
The busy Fuji Speedway circuit was eerily quiet that day which meant I pretty much had the whole pit lane to myself when shooting the Green Tec Kumho IS, the official name of the car.
I love how the front fenders protrude well above the stock hood line of the IS, as if the car was cut around the skirt line and pushed down over the wheels. The test driver was constantly going in and out of the pits to test the suspension adjustments the Shift mechanics were making.
Positioning the engine centrally within the chassis has allowed the IS to obtain an optimal weight balance that benefits every aspect of the car’s handling and performance. As long as the central section of the chassis remains the same as the stock cat it is based on, Super GT regulations allow for custom front and rear tubular structures to be created. The engine and gearbox in this configuration become stressed elements of the chassis; if you look closely you can see how the tubular subframe that originates from the firewall, there to separate the cockpit from the rear of the car, connects directly to the Xtrack sequential transmission behind the engine. This is also where the bell cranks for the in-board push-rod suspension are located. The IS runs the same RV8J Toyota Motorsport engine as used on Formula Nippon single seater race cars. This lightweight, dry-sumped 3L V8 is good for over 550 HP in that configuration, but for the Super GT300 class it is forced to breathe through 24.8 mm air restrictors that drastically lower power to the 300 HP mark every car within the class needs to adhere to. The IS weighs in at 1,200 kg so 300 horses are quite sufficient for some fast lap times, plus one has to remember these cars vehicles are more about handling than outright performance. Check out that massive carbon air scoop that forces air down through the air box, wrapped in gold foil for the best heat insulation possible.
Positioning the engine so low and centrally in the chassis creates a few problems with heat build up, and as you can see the Shift Racing mechanics have taken every measure possible to insulate the titanium headers and surrounding areas.
Super GT stipulates that tires are to be the same size all round, meaning the Tan-ey-sia single-nut forged wheels measure 11Jx18″ front and rear and are shod with 280/710 R18 Kumho Ecsta slicks. More gold insulation as the exhausts runs along the carbon diffuser towards the rear of the car.
The Lexus grille is probably the only thing that is shared with a stock street IS!
I’m a big fan of all those complicated looking rear canards that take advantage of the air flowing around and under the body to increase rear downforce. Mind you the rear wing probably takes care of most of the downforce!
On top of Green Tec and Kumho, Maziora is also a sponsor, and the whole body is painted in a mother-of-pearl hue that shifts shade depending how the light hits it.
When the mechanics took the wheels off it was a perfect opportunity to get a shot of the forged alloy monbloc AP Racing calipers. Carbon discs are not allowed in Super GT. You can also get a glimpse at the custom double-wishbone suspension layout, which is all rose-jointed to allow the geometry to be finely tuned.
Removing the engine up front has left a lot of space to play with. The front outermost area is taken up by the radiator which is housed in a tight fitting carbon box that provides the core with an optimal flow of air, immediately expelled from the hood vents once it has done its job. The rest of the “engine” bay is taken up with the custom front subframe onto which the suspension is mounted.
Here is a closer shot of one of the billet bell cranks that transfers the suspension movements onto the vertically mounted Quantum dampers. You can also see the mounting point of the adjustable stabilizer bar.
Things are pretty cosy for the driver and I’m guessing rather hot with the 3L V8 screaming away behind the carbon-Kevlar Recaro seat!
Everything is within easy reach, from the gear selector for the Xtrac sequuential to the two levers that adjust the front and rear anti-roll bars. LCD and rear-view camera are a must to see what is going on behind.
The IS is able to lap the Fuji Speedway track in the mid 1-minute 40-second range, which makes it about 10 seconds slower than the top GT500 cars like the GT-R, NSX and SC430.
Manabu Orido actually won the 2009 GT300 championship behind the wheel of the Weds Sport IS350…
…making the IS350 a successful replacement to the little MR-S. Hope you enjoyed this look into a modern Super GT car!
-Dino Dalle Carbonare