"New TLX Powertrains
At the heart of the TLX's athletic sports-sedan performance capabilities are two new powertrains, both utilizing direct-injection, i-VTEC valvetrains with variable cam phasing, and low-friction technologies to deliver higher output and more linear and responsive power delivery, as well as to garner class-leading fuel-economy ratings.
The direct-injected 2.4-liter DOHC i-VTEC in-line 4, producing a peak 206 horsepower and 182 lb.-ft. of torque, is mated to an all-new 8-speed Dual Clutch Transmission (8DCT) with torque converter, the world's first transmission of this type to be paired with a torque converter. Featuring Sequential SportShift, closely spaced ratios, ultra-quick shifts and automatic rev-matching downshifts, the 8DCT gives the 2.4-liter TLX an aggressively sporting yet refined feel. The torque converter provides exceptionally smooth operation in stop-and-go situations, plus it offers off-the-line torque multiplication for substantially improved initial acceleration that a DCT alone cannot equal."
Direct-Injected 2.4-liter Inline 4-cylinder Engine
The TLX's new Direct Injection (DI) 2.4-liter DOHC i-VTEC 4-cylinder engine brings a host of intelligent technology to its segment. The engine's i-VTEC system combines VTC (Variable Timing Control), which continuously adjusts the intake camshaft phase, with Variable Valve Timing and Lift Electronic Control (VTEC), which changes valve lift, timing and duration of the intake valves. A new Direct Injection (DI) system, dual-stage intake manifold and other technologies combine to produce up to 10-percent more torque as compared to the same sized engine that is standard in the TSX Sedan, with greater power available over the entire operating range. Peak power (206 horsepower) is also higher than that of the TSX engine, with the peak arriving at 6,800 rpm instead of 7,000 rpm.
Fuel economy ratings are exceptional, due in part to efficient Direct Injection, a new combustion chamber design, offset cylinder bores and a range of friction-reducing technologies. The TLX equipped with the 2.4-liter engine and standard 8-speed dual-clutch transmission has an EPA fuel-economy rating of 24/35/281 mpg city/hwy/combined. That's a significant increase over the smaller TSX sedan, which was rated at 22/31/261 when equipped with an automatic transmission. The 4-cylinder engine meets ULEV-2 emissions standards in select states, and Federal Tier 2, Bin 5 standards. 4-Cylinder Engine Block, Crankshaft and Pistons
The TLX's 2.4-liter engine has a lightweight die-cast aluminum block with a single main-bearing cradle design that creates a rigid assembly to help minimize noise and vibration. Cast-in iron cylinder liners provide long-lasting durability. Each journal on the forged-steel crankshaft is micropolished to reduce internal friction. To improve smoothness throughout the rpm range and help lower noise levels, the engine is fitted with an internal balancer unit. Consisting of a pair of chain-driven counter-rotating shafts located in the lower block and integrated into the oil pan, the balancing system helps quell the inherent second-order harmonic vibrations that normally impact inline 4-cylinder engines.
To reduce piston-sliding friction, the cylinder bores are offset by 8.0 mm from the crankshaft. This gives the connecting rods a more favorable angle during each power stroke, which reduces side loading on the pistons and in turn, improves efficiency. The engine features a forged crankshaft for high rigidity and low friction. Lightweight pistons have a carefully optimized skirt design to minimize reciprocating weight, and reduced weight minimizes vibration and increases operating efficiency. The piston crowns are dished, to help maintain stable combustion and to optimize distribution of the stratified fuel charge from the direct injector in each cylinder. This close control over the combustion process boosts overall operating efficiency. 4-Cylinder Dual-Stage Intake Manifold
To maximize power output, the 2.4-liter engine has a dual-stage intake manifold has two different intake runner lengths that are selected based on the operating conditions. An actuator and a set of four butterfly valves control the intake runner switching process. At low engine speeds, the long runners are used to improve low-end torque. At higher engine speeds the system switches to the short intake runners for greater high rpm power. The result is intake tuning that is optimized for the engine's entire operating range. 2.4-liter Engine Cylinder Head and Valvetrain
The lightweight cylinder head is made of pressure-cast aluminum alloy, with exhaust passages cast directly into the cylinder head. This eliminates the need for a traditional separate exhaust manifold and allows the close-coupled catalytic converter to be mounted directly to the cylinder head.
A silent-chain drives the dual overhead cams and features a double-arm tensioner design that reduces operating friction. The cam drive is designed to be maintenance free throughout the life of the engine.
To help boost fuel efficiency and power, the combustion chamber shape and valve angles have been optimized. The included valve angle is a narrow 35 degrees, which decreases the surface-to-volume ratio and helps create a flatter, more compact combustion chamber that reduces unburned hydrocarbon emissions. With this combustion chamber shape and the precise control of direct injection, the compression ratio set at 11.6:1.
The cylinder head features a new "tumble port" intake design. In combination with the new combustion chamber and piston crown shape, the design's high level of airflow tumble helps create a homogenous fuel mixture for low fuel consumption and high airflow for high power output. 2.4-Liter Enginei-VTEC Valve Control System
The TLX's direct-injected 2.4-liter DOHC 16-valve i-VTEC engine uses an advanced valve-control system to combine high power output with high fuel efficiency and low emissions. The system combines VTC (Variable Timing Control), which continuously adjusts the intake camshaft phase, with Variable Valve Timing and Lift Electronic Control (VTEC), which changes valve lift, timing and duration of the intake valves.
At low rpm, the VTEC intake valve timing and lift are optimized for high torque and low fuel consumption.. As engine rpm builds past 4,900 rpm, the VTEC system transitions to a high-lift, long-duration intake cam profile for superior high-rpm engine power.
The "intelligent" portion of the system is its ability to continuously vary the timing of the intake cam relative to that of the exhaust camshaft. This helps boost power and also provides a smoother idle (allowing idle speed to be reduced). The intake cam timing is varied based on input from sensors that monitor rpm, timing, throttle opening, cam position and exhaust air-fuel ratio. The result is increased fuel efficiency and lower NOx emissions.
There's also a new Acura TV ad where a guy is test driving a white TLX 2.4 with technology package. The dealership explains to him that VTEC kicks in at higher RPMs (the ad makes the TLX sound like a Civic Si than a luxury car actually).
cast iron cylinder sleeves??? **** i want to push some boost through this motor lol jackson racing come out with a super charger yet? with 11.6:1 compression it would make great power off of little boost.