Like VW and Audi's FSI, and nearly all modern common-rail diesels,
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| Only 5.4 seconds to spare? That's all the time needed for the Solstice GXP to get you to 60 mph. (Photo: General Motors) |
SIDI benefits the engine by turning highly pressurized gasoline into a fine mist, which is then directly injected into the combustion chamber. In a super-fine, atomized state, less fuel is needed to cause ignition, allowing it to safely run lean, which makes it more efficient than regular engines. The Solstice GXP is EPA rated at 20 mpg city and 27 mpg highway, impressive for a sports car with such a superb performance potential.
While SIDI and VVT help to boost power, the magical number of 260 was reached mainly by the engine's turbocharging system. Traditionally, it took a turbocharger the size of a watermelon to make the 20 psi of boost the GXP has, but these kinds of turbos are avoided because of their lag. Instead, the engine employs a lightweight, twin-scroll system that spools very quickly, and is allied to an air-to-air intercooler to make throttle response instantaneous.
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| Solstice equipment levels go up with GXP including StabiliTrak, ABS, power windows, mirrors and keyless entry. (Photo: General Motors) |
With the new engine under the hood, revised springs and dampers at all four corners, a limited slip differential at its tail, and StabiliTrak stability control keeping watch, Pontiac has made a tiger out of the 'cute' little Solstice. Mated to either a close-ratio five-speed manual or a five-speed automatic, GM claims that the Solstice GXP can reach 60 mph in under 5.4 seconds. Top speed has yet to be disclosed, but it should be at least 145 mph, or more. Completing the package are subtle new front and rear fascias, 18-inch wheels, and chromed exhaust tips, on the exterior, plus red interior trim stitching and GXP gauges added to the instrument cluster, inside.
