2006 Subaru Impreza WRX STi spec C
The spec C is Subaru’s homologation model which features slight improvements over the standard spec model for racing in the Production World Rally (PWRC) and Group N rally. A minimum number of 1000 cars were needed to satisfy the requirements, so Subaru Technical Institute offered them to the Japanese market.
The big difference between a spec C and other WRXs is a substantial (90 kg) reduction in weight thanks to lighter glass, thinner roof construction and an aluminum trunk lid.
Benefiting the race cars, are new suspension pickups and beefier McPherson strut arrangements with braces to improve rigidity.
Other small details include, power window delete on the rear windows, manual control center of the center differential, larger disc brakes, ball bearing turbochargers, 12L tank for intercooler, transmission oil cooler, Fuel pump with rotating chamber, Air-cooled engine oil cooler, spec C exclusive front/rear stabilizer and a Roof ventilator.
To help increase sales of the spec C, a special RA-R version with a 320 bhp version was released in Nov of 2006.
In Detail
| submitted by | Richard Owen |
| engine | EJ20 Boxer-4 |
| aspiration | Twin IHI, Ball Bearing Turbochargers |
| valvetrain | DOHC, 4 Valves per Cyl w/AVCS VVT |
| fuel feed | Multipoint Fuel Injection |
| displacement | 1994 cc / 121.7 in³ |
| bore | 92 mm / 3.62 in |
| stroke | 75 mm / 2.95 in |
| compression | 8.0:1 |
| power | 205.8 kw / 276 bhp @ 6400 rpm |
| specific output | 138.42 bhp per litre |
| bhp/weight | 165.77 bhp per tonne |
| torque | 422 nm / 311.3 ft lbs @ 4400 rpm |
| body / frame | GH-GDB Unit Steel |
| driven wheels | AWD w/Driver Control Center Diff (DCCD), Front and Rear LSD |
| wheel type | BBS Forged Alloys |
| front tires | 235/45ZR17 POTENZA RE070 |
| rear tires | 235/45ZR17 POTENZA RE070 |
| front brakes | Discs w/ABS, EBD |
| f brake size | x 323 mm / x 12.7 in |
| rear brakes | Discs w/ABS, EBD |
| r brake size | x 312 mm / x 12.3 in |
| front wheels | F 43.2 x 20.3 cm / 17 x 8 in |
| rear wheels | R 43.2 x 20.3 cm / 17 x 8 in |
| steering | Quick Ratio Rack & Pinion |
| f suspension | MacPherson Struts w/Lower L Arms |
| r suspension | MacPherson Struts w/Trailing Arms |
| curb weight | 1665 kg / 3671 lbs |
| wheelbase | 2540 mm / 100 in |
| front track | 1491 mm / 58.7 in |
| rear track | 1496 mm / 58.9 in |
| length | 4465 mm / 175.8 in |
| width | 1740 mm / 68.5 in |
| height | 56.3 mm / 1425 in |
| transmission | 6-Speed Manual |
| gear ratios | 3.636:1, 2.375:1, 1.761:1, 1.346:1, 0.971:1, 0.756:1, :1 |
| final drive | 3.900:1 |
