The 2007 Nissan Sentra SE-R front wheels are powered by a 2.5-liter four-cylinder engine with variable valve timing. In the standard SE-R, this engine produces 177 horsepower and 172 lb-ft of torque at 2800 rpm. This version of the engine is connected to a continuously variable transmission (CVT) that the driver can control with paddle shifters mounted on the steering wheel. The Spec V offers a higher compression ratio, stronger rods, a different camshaft profile and other refinements to up the power to an even 200 horses. Torque increases to 180 lb-ft at a much higher 5200 rpm. The Spec V comes only with a close-ratio 6-speed manual transmission.