To keep up the battle with the V6-powered Mustang, GM announced a new V6 powerplant for the 2012 Chevrolet Camaro with 323 hp.
This new 3.6 liter LFX V6 develops an SAE-certified 323 horsepower (241 kW) at 6,800 rpm – 11 horsepower (8 kW) more than 2011 models. It features direct-injection and number of other new technologies to improve performance, efficiency and durability. What’s more it’s also lighter than the previous unit by 20.5 pounds (9.3 kg) and that improves handling and efficiency as well.
Other fuel saving features include DOHC, four valves per cylinder, continuously variable valve timing while it employs an array of emissions control systems such as evaporative emissions system, catalytic converter, equal-length exhaust, dual close coupled and dual under floor catalytic converters, positive crankcase ventilation, intake and exhaust cam phasers, electronic throttle control.
Now, buckle up for some deep technical details on the new LFX engine. Warning: You might get bored to death!
The 3.6L is a 60-degree design, with the cylinder block and cylinder heads cast in aluminum for low weight. A forged steel crankshaft provides optimal strength in the bottom end, while the cylinder heads include four valves per cylinder, with a dual overhead camshaft design incorporating infinitely variable cam phasing. Compared to the 3.6L V-6 in 2011 models, the new LFX engine features:
- New cylinder head design with integrated exhaust manifold
- Improved intake port design and larger intake valves within the cylinder heads
- Longer-duration intake camshafts
- Composite intake manifold
- New fuel pump and isolated fuel rail
- New, optimized-flow fuel injectors
- Structural front cover and cylinder block enhancements
- Stronger and lighter-weight connecting rods
- Camshaft cap and throttle body design enhancements.
The LFX engine is significantly lighter than the current 3.6L V-6. The integrated cylinder head/exhaust manifold design saves approximately 13 pounds (6 kg) per engine over the cylinder heads and manifolds of the current engine, while the new composite intake manifold saves approximately 5.5 pounds (2.5 kg) over the current aluminum intake. Additionally, a lighter-weight structural front cover and lighter-weight, high-strength connecting rods bring the total weight savings to 20.5 pounds (9.3 kg), which helps the vehicle’s fuel efficiency and enhances its feeling of driving balance.
“It isn’t often we get the opportunity to take more than 20 pounds off an engine. We met some aggressive targets while retaining great strength and reliability,” said Haider. “The engine is as durable as ever but now with improved performance and efficiency.”
Additionally, the optimized-flow fuel injectors and integrated exhaust manifolds/cylinder heads promote lower emissions. And along with its weight savings, the composite intake manifold has a smaller radiated surface area to help it maintain noise and vibration characteristics comparable to the previous aluminum manifold.
Greater airflow brings more power – and efficiency
The new cylinder heads also bring a revised intake port design that enhances airflow to the combustion chambers. Larger-diameter intake valves (38.3 mm vs. 36.96 mm) are used in the heads and work in conjunction with new, longer-duration intake camshafts to provide the engine’s boost in horsepower.
The valves let air in and exhaust escape from the combustion chambers. The duration of the camshaft determines how long the valves are open. By using larger valves and holding them open longer, more of the air is pulled into the combustion chamber, for a more powerful combustion. Often, the tradeoff for greater power is greater fuel consumption, but the LFX engineers adapted new fuel injectors that are optimized for the engine’s performance parameters. The result is more power without sacrificing fuel economy. The more-efficient combustion also means reduced emissions.
Of course, the LFX engine retains direct fuel injection. It optimizes fuel delivery to the combustion chamber by introducing fuel closer to the combustion chamber. The result is better efficiency in the combustion process leading to increased fuel efficiency at part and full throttle.
The LFX uses a new fuel pump for the direct injection system, along with a new, isolated fuel rail. The new fuel pump is quieter, while the isolated fuel rail further reduces fuel system noise.
Greater refinement and durability
Additional changes incorporated in the LFX deliver greater refinement, quietness and durability, starting with revisions to the front cover. It was redesigned with additional support ribs on the backside and an additional fastener to reduce noise and vibration. The cylinder block is modified slightly to accommodate the front cover’s additional fastener.
Inside the engine, the powdered metal connecting rods use a higher ratio of copper, which makes them stronger and enables further mass savings. Also, the camshafts feature new saddle-type caps for improved durability. Finally, the throttle body is updated with a new, digital throttle position feature that eliminates a previous mechanical contact for more trouble-free operation.