New friction reducing ball bearings for the twin-scroll turbocharger and a reprogrammed ECU increases maximum torque and improves accelerating performance. An aluminum hood, laminar window glass and a downsized battery result in a lower body weight.
Sadly the spec C is only for Japan.
FHI launched the Subaru Impreza WRX STI spec C
Tokyo, December 21, 2010 – Fuji Heavy Industries Ltd. (FHI), the maker of Subaru automobiles, today introduced the “Subaru Impreza WRX spec C”, a new addition to the current WRX STI line-up. The model goes on sale today through Subaru dealerships in Japan.
Based on the Impreza WRX STI, the iconic sport model of Subaru, the WRX STI spec C model features enhanced engine and chassis performance as well as a lighter body on the premise of driving in motor sports. The model further strengthens its presence in the high performance car arena by offering sheer excitement and unique driving sensations as a distinctive sport model, in line with the performance level originally delivered by the Impreza WRX STI.
The twin scroll turbocharger newly adopted ball bearings for the turbine axle bearing, and the ECU (Engine Control Unit) program was also exclusively tuned. Thus the engine of the spec C model increases the maximum torque, and provides quicker response and improved accelerating performance. The adoption of an aluminum engine hood, laminar window glasses and a downsized battery resulted in a lighter body, which further refines the model’s driving performance. Thanks to its specially tuned front & rear suspensions, the chassis offers stable and linear driving control even in marginal driving conditions.
Subaru further enhances the WRX STI line-up by introducing this STI spec C model, in addition to the regular WRX STI model and STI A-Line model, the AT version.
Enhancement of Engine performance:
-Ball bearings of the turbine axle were newly adopted to reduce friction in the turbocharger. With the optimized ECU programming, the engine increases the maximum torque by 8 Nm, compared to the base WRX STI model, and it offers smoother and quicker response to the accelerator pedal and excellent accelerating performance.
-An inter-cooler water spray prevents rise in intake-air temperature at continued high-load driving, providing stable engine performance and improved efficiency.
Subaru Impreza WRX STI spec C Enhancement of Chassis performance:
-Reinforcement of the cross member in front-suspensions offers a linear steering response.
-Rear LSD (Limited Slip Differential) system was changed to a mechanical type from a Torsen type to obtain the steady and powerful traction during cornering.
-Bridgestone “POTENZA RE070” (245/40R18) were adopted to enhance cornering ability and higher grip performance, especially in dry conditions.
-Nimble handling with a firm steering feel is assured by increasing oil flow volume in the power steering system.
-An aluminum engine hood and a downsized battery, which make the front section of the vehicle lighter, produce better maneuverability.
-Laminar glasses were adopted in the front and side windows. They lightened the upper section of the body weight, resulting in improved stability during cornering.
-Newly-designed lightweight 18-inches alloy wheels are standard to offer excellent road-hugging property by reducing unsprung weight.
-A structural change of fuel pomp provides stable fuel delivery even on high-load driving.
-Gold colored “brembo” brake calipers are standard.
-The front bucket seats (fabric with red stitch) are standard on models with 18-inches alloy wheels.
-The “RECARO” seats are optional with SRS front side airbags and SRS curtain airbags on models with 18-inches alloy wheels.
-Engine type: Horizontally-Opposed 4-cylinder DOHC 16-valve turbocharged engine
-Displacement: 1,994 cc
-Maximum output: 227kW (308 PS)/6,400 rpm
-Maximum torque: 430 Nm (43.8 kgfm)/4,400 rpm
-Turbo type: Ball-bearing type twin scroll turbocharger