For 2012, the 2.4-liter DOHC i-VTEC® inline four-cylinder engine remains as the standard engine. The engine offers good acceleration while generating excellent fuel efficiency. The all-aluminum I-4 engine produces 201 hp and 172 pound-feet of torque (6MT), and incorporates Acura's i-VTEC® 'intelligent' valve control system that features Variable Valve Timing and Lift Electronic Control (VTEC®) combined wîth Variable Timing Control™ (VTC™). Though peak horsepower is virtually unchanged versus the previous generation 2.4L engine, peak torque output has risen by 8 lb-ft. In addition, the engine's torque curve has fattened considerably. Horsepower, for example, is up five percent at 4,400 rpm. The result is stronger throttle response and better acceleration just about everywhere in the engine's operating range. To achieve these power gains, the engine has a higher compression ratio, different valve timing, and intake and exhaust flow improvements. An aluminum and resin composite intake manifold reduces weight over the previous I-4's aluminum design, while better insulating the engine's incoming airflow from under-hood heat.
The use of numerous friction reducing technologies (applied to both the 2.4L I-4 and the 3.5L V-6 engines) help reduce internal operation friction which helps deliver improved efficiency.
Both the 4- and 6-cylinder engines make use of a plateau honing technique for the cylinder bores that generates a smoother surface. As a result, the piston rings achieve more consistent contact wîth the cylinder walls which generates improved ring-to-bore sealing along wîth reduced overall friction.
With the 2.4L I-4, the pistons make use of a low-tension piston ring that reduces operating friction while the 3.5L V-6 uses a redesigned ion-plated piston ring design. In addition, the outer skirts of both the 4- and 6-cylinder pistons now feature a molybdenum coating applied in a unique dot-pattern application. The result is reduced overall friction as the pistons move within the cylinder bores.
Other friction reducing items include the use of lower viscosity engine oil (0W-20 weight versus the previous 5W-20 weight oil) along wîth lower viscosity oil for the Sequential SportShift 5-speed automatic transmission. (posted on conceptcarz.com) In addition, the 5-speed automatic fitted to the 2.4L I-4 engine makes use of a fluid warmer assembly warmer that helps improve shift quality and engine fuel economy for TSX owners who live in colder climates.
A rear-mounted exhaust system layout, close-coupled catalytic converter and advanced Programmed Fuel Injection (PGM-FI) team to help both the I-4 and V-6 engines meet EPA 2 - Bin 5 and CARB LEV II Últra Low Emission Vehicle standards. ( posted on conceptcarz.com)
Beginning in 2010, the TSX was available wîth a transversely mounted 3.5-liter all-aluminum V-6 engine wîth single overhead camshaft (SOHC) cylinder heads. The V-6's 12 intake valves are actuated by Acura's acclaimed VTEC® (Variable Valve Timing and Lift Electronic Control) system. The compact and efficient V-6 engine produces 280 horsepower and 254 lbs-ft of torque. The power curve has been specially tailored to deliver strong, linear power in the rpm range used in most day-to-day driving conditions.