HHR buyers wanting a little more oomph under the right foot will need to opt for an upgrade in 1LT trim, or the 2LT package
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| Chevy has made no mention of an SS version, which would probably feature GM's 205-horsepower turbocharged 2.2L four. (Photo: General Motors of Canada) |
that offers GM's 2.4L 4-cylinder as standard equipment. The larger displacement engine produces 170-horsepower and 170 lb-ft of torque, which should be ample to give the lightweight crossover spirited performance. Still, Chevy has made no mention of an SS version, which would probably feature GM's 205-horsepower turbocharged 2.2L four, as currently offered in the Saturn ION Red Line and will soon arrive in the upcoming Cobalt SS coupe. This would allow the HHR to compete more directly with the 220-horsepower "GT Cruiser".
While not quite as powerful as Chrysler's 2.4-liter four, the GM engines have been upgraded to reduce noise, vibration and harshness (NVH). The pistons, for instance, feature a polymer coating and skirt design to reduce noise during cold startup, while a new, two-layer acoustic engine cover has been added, which reduces noise. I've experienced the General's enhanced 2.2L engine in the Cobalt and Pursuit, and can attest to it being a serious improvement over that used in the previous Cavalier/Sunfire. The engine also includes a new automatic timing chain tensioner designed to maintain optimal tension and a resultant NVH reduction.
The engine's general architecture includes dual overhead camshafts (DOHC), four valves per cylinder, twin counter-rotating balance shafts, electronic
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| A Getrag F23 5-speed manual transmission, featuring synchros on all five forward gears as well as reverse, will be standard. (Photo: General Motors of Canada) |
throttle control, a low-friction roller-finger follower valvetrain with hydraulic lash adjusters, low-maintenance chain-driven camshafts, direct-mount accessories, that latter to reduce or eliminate traditional sources of noise and vibration, a full-circle transmission mount to reduce NVH, GM's Oil Life System, to reduce the frequency of oil changes, a cast-in oil filter housing, which makes it unnecessary to crawl under the HHR to perform oil changes while eliminating throwaway oil filter cans that retain used oil, which is better for the environment, plus a catalytic converter positioned next to the exhaust manifold to accelerate catalyst "light off," reducing hydrocarbon emissions.
