Porsche direct injection 911
Thursday July 17, 2008
Porsche have launched their first direct injection road car engines in the 997 911 model. The Porsche 911 Carrera and Porsche 911 Carrera S models are the first to benefit from the technology.
The 911 Carrera engine has new internal dimensions, with a bore of 97.0 mm (up from 96.0 mm) and a stroke of 81.5 mm (down from 82.8 mm), giving a total swept capacity of 3614 cc (from 3596 cc). The use of the direct petrol injection system allows for a higher compression ratio, up to 12.5 from 11.3. The result of all these changes is 20 more PS (345 PS versus 320 PS), peaking 300 rpm sooner in the rev range, now at 6500 rpm. Torque is up as well, from 370 Nm at 4250 rpm to 390 Nm at 4400 rpm. These changes result in 0.1 second shaved from the 0-100 km/h sprint, which is completed now in a claimed 4.9 seconds, 4 km/h additional top speed (289 km/h) and a standing kilometre time 0.2 seconds better (23.6 seconds claimed).
Similar changes are found in the 911 Carrera S. The bore and stroke are more radically changed, with bore up 3 mm to 102.0 mm, and the stroke is shorter by 5.3 mm, now at 77.5. These dimensions give the flat six engine a swept capacity of 3800 cc, 24 cc down on the indirect injection 911 Carrera S model. The compression is up too, from 11.8 to 12.5, as in the Carrera models. The power and torque peaks of the new engine are now 385 PS at 6500 rpm (from 355 PS at 6600 rpm) and 420 Nm at 4400 rpm (400 Nm at 4600 rpm previously). These improvements mean a claimed to speed of over 300 km/h for the 911 Carrera S - 302 km/h is the figure quoted by Porsche, up from 293 km/h for the indirect injection model. The 0-100 km/h dash is covered in 4.7 seconds, unchanged from the previous 911 Carrera S.
The other big change in the 997 911 range is the introduction of the PDK - Porsche-Doppelkupplung - transmission, replacing the old Tiptronic gearbox option. This is a twin clutch sequential manual 'box, with fully automatic mode available. Due to optimised change points and adaptive technology, the double clutch transmission is said to improve economy and performance over the manual versions.
The 911 Carrera engine has new internal dimensions, with a bore of 97.0 mm (up from 96.0 mm) and a stroke of 81.5 mm (down from 82.8 mm), giving a total swept capacity of 3614 cc (from 3596 cc). The use of the direct petrol injection system allows for a higher compression ratio, up to 12.5 from 11.3. The result of all these changes is 20 more PS (345 PS versus 320 PS), peaking 300 rpm sooner in the rev range, now at 6500 rpm. Torque is up as well, from 370 Nm at 4250 rpm to 390 Nm at 4400 rpm. These changes result in 0.1 second shaved from the 0-100 km/h sprint, which is completed now in a claimed 4.9 seconds, 4 km/h additional top speed (289 km/h) and a standing kilometre time 0.2 seconds better (23.6 seconds claimed).
Similar changes are found in the 911 Carrera S. The bore and stroke are more radically changed, with bore up 3 mm to 102.0 mm, and the stroke is shorter by 5.3 mm, now at 77.5. These dimensions give the flat six engine a swept capacity of 3800 cc, 24 cc down on the indirect injection 911 Carrera S model. The compression is up too, from 11.8 to 12.5, as in the Carrera models. The power and torque peaks of the new engine are now 385 PS at 6500 rpm (from 355 PS at 6600 rpm) and 420 Nm at 4400 rpm (400 Nm at 4600 rpm previously). These improvements mean a claimed to speed of over 300 km/h for the 911 Carrera S - 302 km/h is the figure quoted by Porsche, up from 293 km/h for the indirect injection model. The 0-100 km/h dash is covered in 4.7 seconds, unchanged from the previous 911 Carrera S.
The other big change in the 997 911 range is the introduction of the PDK - Porsche-Doppelkupplung - transmission, replacing the old Tiptronic gearbox option. This is a twin clutch sequential manual 'box, with fully automatic mode available. Due to optimised change points and adaptive technology, the double clutch transmission is said to improve economy and performance over the manual versions.
