The last Audi quattro concept was brilliant: dashing lines, furious power, low weight. But despite hints that it might see production, nothing ever came of the car. That may change.

It may not change, too. But here we have the new Audi Sport quattro concept, previewed ahead of its Frankfurt auto show debut, where it will once again tempt our souls with possibility.

There are, once again, rumors that the new Sport quattro concept may lead to a production vehicle, likely in fairly limited volumes, perhaps priced at or above the R8 V10's $180,000 tag.

But all of that is, for now, speculation.

It's hopeful speculation, however, as the new car seriously one-ups the old one with a new hybrid drivetrain rated at 700 horsepower combined. Maximum torque: 590 pound-feet. It also one-ups the car in another, less desirable, respect.

The engine portion of the new hybrid drivetrain is a four-liter twin-turbo V-8 good for 560 horsepower and 516 pound-feet on its own. The electric motor is rated at 110 kW and 295 pound-feet. All power is directed through a modified eight-speed tiptronic automatic to all four wheels through quattro all-wheel drive (naturally). A 14.1-kWh lithium-ion battery powers the hybrid system.

Audi Sport quattro concept, 2013 Frankfurt Auto Show

Audi Sport quattro concept, 2013 Frankfurt Auto Show

A cylinder deactivation system turns of four cylinders under partial loads, and start-stop completes the trio of fuel-saving powertrain technologies.

The end result is up to 31 miles on electric power alone and 94 mpg, while also reaching 0-62 mph in 3.7 seconds and a top speed of 190 mph.

However, weight has ballooned tremendously from the 2,866-pound curb of the prior concept. Now, the hybrid Sport quattro concept is a beefy (but perhaps less imaginary) 4,079 pounds.  

Twenty-one-inch wheels wrapped in 285/30 tires all the way around apply the massive hybrid torque to the ground--and hold up the massive hybrid's bulk.

We'll have live photos of the Sport quattro concept fresh from the Frankfurt show floor later this month, so be sure to follow our Frankfurt auto show page.