HOLDEN might have to look no further than its own proving ground if its wants inspiration for a more powerful V6 Commodore any time soon.
Fellow General Motors brand Chevrolet has announced a 241kW/377Nm high-performance version of the GM global 3.6-litre V6 for its image-leading, Holden-engineered Camaro in a 45th anniversary edition to go sale in the United States in the next few months.
The normally aspirated, direct-injection engine produces 31kW or 15 per cent more power than the premium 210kW/350Nm SIDI (Spark Ignition Direct Injection) variant of GM’s V6 that powers Holden’s Commodore.
As Holden is the engineering home room for all Zeta-based rear-drive cars for GM, chances are that Camaros bearing the new engine have been running around the Lang Lang proving ground in Victoria for some time.
Holden spokesman Jonathan Rose told GoAuto that Holden had “no plan to change from our current SIDI V6 range at this point in time”.
Holden is working on its new VF Commodore for launch in about 2014, when a Chevrolet-badged variant, dubbed ‘SS Sedan’, is rumoured to be on the cards for debut in the United States.
Left: GM's 241kW V6 and the 45th anniversary Chevrolet Camaro.
The standard Camaro already runs a more powerful 233kW version of the normally aspirated V6, while V8 variants are powered by a 300kW/560Nm version of GM’s LS3 6.2-litre powerplant.
The new hi-po version of the V6, dubbed LFX, will power the 45th Anniversary Special Edition Camaro to celebrate the 45th birthday of GM’s muscle car, which so far this year is outselling its arch-rival, the Ford Mustang.
The V6 achieves peak power of 241kW at 6800 rpm, becoming the most powerful version of GM global V6 by edging out the previous champion, the Holden-made 2.8-litre twin-scroll turbocharged V6 that achieves 239kW in the Opel/Vauxhall Insignia VRX. The Cadillac CTS has the most powerful current normally aspirated version of the V6 in the US, at 237kW and 373Nm.
The Camaro V6 is not only more powerful but 9.3kg lighter than the standard 3.6, courtesy of a composite intake manifold (replacing the cast aluminium intake), exhaust manifolds integrated with the cylinder heads and lightweight, high-strength conrods.
Other enhancements include a new cylinder head design with an integrated exhaust manifold, larger intake valves, re-designed intake ports, new fuel pump, isolated fuel rail, optimised fuel injectors, new camshaft cap and altered throttle body.
Chevrolet said the new fuel injectors and integrated exhaust manifolds/cylinder heads promote lower emissions, while the composite intake manifold cuts noise and vibration (NVH) levels.
A stiffer front engine cover with an extra fastener also helps to cut engine NVH, while the cylinder block has been redesigned to accommodate it.
The larger-diameter intake valves (38.3mm v. 36.96mm) work in conjunction with a new, longer-duration intake camshaft profile to provide the engine’s boost in horsepower. To avoid a lift in fuel consumption, fuel flow to the direct injectors has been adjusted.
Chevrolet claims the new fuel pump and isolated fuel rail are quieter than existing systems.
Chevrolet’s assistant chief engineer for V6 engines, Ameer Haider, said the enhancements would not only deliver greater power and reduced weight but also lower emissions.
“This is a great engine architecture and our engineers have never stopped working to make it even better,” he said.
The 2012 Camaro will also marks the debut of a sportier FE4 suspension on the SS coupe, promising flatter cornering, a more neutral balance during hard turns and minimised understeer at the limit.
The FE4 package includes retuned front and rear dampers, new solid front (23mm) and rear (24mm) stabiliser bars and 20-inch alloy wheels with bigger front (P245/45R20) and rear (P275/40R20) tyres.
The stabiliser bars have been repositioned outboard of the damper mounts as part of the tweaked suspension geometry.
Inside, the 2012 Camaro will get a fresh instrument panel with new graphics and trim, as well as a sportier steering wheel and power lift for the front passenger seat.
A rear-view camera and new rear spoiler will be standard equipment on all Camaros.