Originally Posted by AutoBlog

The Chevrolet Volt mystery may have unfolded just a bit more as GM-Volt.com is reporting that GM CEO Rick Wagoner has confirmed that the General is considering a 1.4L four cylinder engine for the production Volt. So far, nothing official has been announced, but the decision to use the 1.4L engine would make plenty of financial sense. After all, it's the same engine that is expected to power the first-generation Chevy Cruze, which may actually follow the Volt to market. Both the Volt and the Cruze will sit atop the next Delta platform, another bit of cost savings. We'd imagine that Chevy could drop the turbocharger and run the engine on the Atkinson cycle while still making plenty of power for this application.

GM has promised fuel mileage of around 50 mpg when operating in range-extended mode as the engine provides the power for the electric motor's operation. Equivalent miles per gallon will be highly dependent on the final output of the lithium battery pack, and the engine still won't be required for the first 40 miles of operation. What's more, the internal combustion engine will have little to do with actual performance numbers like acceleration or top speed. Therefore, we don't really care what engine GM chooses for the Volt so long as its original mileage targets aren't sacrificed along the way.

[Source: MLive.com via GM-Volt.com]