Here's your guide to all 21 different versions of the Porsche 911

On Tuesday, Porsche rounded out the 911 family with the introduction of its latest track-bred GT3 variant at the 2017 Geneva Motor Show.

At the heart of the new Porsche 911 GT3 is a 4.0 liter, naturally aspirated flat-six-cylinder engine producing 500 horsepower and 339 lb.-ft. of torque. As a result, the GT3 becomes the first of the 991.2 generation 911s to eschew turbocharging.

Customers can option the GT3 with either a traditional six-speed manual transmission or a seven-speed twin-clutch PDK unit.

The 2018 Porsche 911 GT3, which is expected to reach US showrooms this fall with a starting price of $143,600, is available with active rear-wheel steering and carbon fiber aerodynamic elements.

According to Porsche, the PDK-equipped GT3 can sprint to 60mph in just 3.2 seconds and reach a top speed of 197 mph. In six-speed guise, the Porsche requires 3.8 seconds to reach 60mph before hitting 198 mph.

Even though, the six speed is slower off the line, the holy combination of a clutch pedal with a naturally aspirated powerplant will be too much of a draw for Porsche purists to ignore.

There are few cars in the world more iconic than the Porsche 911. Over the years, the rear-engined sports car has gotten bigger, faster, and more technologically advanced. But its spirited driving dynamics and on-track capabilities have continued to make it a favorite among enthusiasts worldwide.

However, you often hear the complaint that all current 911s pretty much look same. And if you ask critics such as ex-"Top Gear" host and longtime newspaper columnist Jeremy Clarkson, he'll tell you that all Porsche 911s since the model's debut in 1963 look identical.

The truth is, most of the various versions of the current generation of 911s do look similar, but they can all be identified by numerous subtle, but important differences.

Like Taco Bell in the fast-food industry, what Porsche has managed to do so successfully is create multiple iterations of the 911 by mixing and matching the same ingredients, and packaging them in a lot of different ways. And if you've ever driven a 911, you'll probably agree with me in saying ... there's absolutely nothing wrong with that.

So here it is - the most current lineup of Porsche's 911 Taco Bell menu.