When they're feeling confident, automakers boast about their specs, ratings, and performance with direct comparisons to the competition.

It's horsepower for specialty cars like the perennial Camaro-Mustang duel, but increasingly for mainstream and green cars, it's miles per gallon.

Yesterday, we sat up and took notice when Ford quietly announced that its upcoming 2013 Ford C-Max Energi plug-in hybrid would best not only the 2012 Toyota Prius Plug-In Hybrid, but also--surprisingly--the Chevrolet Volt range-extended electric car.

Better on MPGe and range

It said the Energi would beat both those cars on the "MPGe" gas-mileage equivalence rating for electric running and in total overall driving range, which Ford quoted at more than 500 miles for the 2013 C-Max Energi plug-in hybrid.

It's hard to judge how seriously to take this claim, since Ford has been startlingly opaque on details and specifications of the C-Max Hybrid and Energi.

We know that the pair will use a 2.0-liter four-cylinder engine tuned to run on the Atkinson Cycle for maximum efficiency, smaller than the 2.5-liter four in the 2012 Ford Fusion Hybrid and Escape Hybrid.

No specs provided, so...

Ford has not issued power or torque ratings for that engine, nor has it given the power of the electric motor-generators, the combined output of the powertrain, the Energi's electric range, or even the energy capacity of the two cars' lithium-ion battery packs.

Given all that, take the claim as it is: Ford trash-talking the competition without much backup thus far.

2012 Chevrolet Volt

2012 Chevrolet Volt

The 2012 Chevy Volt is rated at 94 MPGe by the EPA, though a comparable figure hasn't been been published for the 2012 Prius Plug-In Hybrid, which will arrive in Toyota dealerships next spring.

Chevrolet quotes a range of "375 miles" for the 2012 Volt in gasoline mode, plus the EPA figure of 35 electric miles. Toyota says total range is "up to 475 miles" for the plug-in Prius.

Prius, OK; Volt, hmmmm

The 2012 Prius Plug-In has an electric range of just 9 to 13 miles. The EPA gives the Volt a 35-mile electric range, and rates it at 37 mpg (on premium gasoline) once the range-extending 1.4-liter engine switches on to run the generator that sends electricity to its electric drive motor.

In discussing the 2013 Ford C-Max Hybrid and C-Max Energi plug-in, Ford engineers repeatedly stress its efforts to maximize efficiency throughout every aspect of the vehicles.

The engine has no accessory drive belts at all, with not only air conditioning but even the water pump running electrically. And the vehicle spends 10 percent more time in electric mode than the previous generation Ford hybrid system, according to John Davis, lead nameplate engineer for the C-Max pair.

High MPGe, low volume?

Still, it's important to note that of the three vehicles, the C-Max Energi plug-in hybrid may have the lowest production volume. Chevrolet has said it plans to sell 45,000 Volts during 2012, and Toyota is rumored to expect sales of up to 10,000 plug-in Priuses. (It will likely sell about 135,00 Prius hatchbacks and Prius V wagons in 2011.)

2012 Toyota Prius Plug-In Hybrid, production model

2012 Toyota Prius Plug-In Hybrid, production model

But Ford says it will be able to build roughly 100,000 "electrified" cars once it's up to full production in 2013. That includes the 2012 Ford Focus Electric battery car, the C-Max Hybrid and Energi plug-in, plus the current Ford Fusion Hybrid and Lincoln MKZ Hybrid.

Assuming 80 percent of that number is conventional hybrids, and 5 percent is the Focus Electric, that leaves a maximum of 15,000 plug-in hybrids for 2013 among the C-Max and any other models Ford may introduce with the same powertrain.

So it's possible that the vehicle with the best overall MPGe rating will be the one that's least available. The hybrid C-Max will arrive sometime next fall, with the plug-in Energi version "a couple of months" after that.

What do you think?

Who do you think will win the showdown in gas-mileage ratings among vehicles that both plug in and have gasoline engines?

Leave us your thoughts in the Comments below.


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