You are aware of the tool they call Google, yes?

The number

fast, faster, the fastest

About $100-200k

GT2 RS is the top track car Porsche makes on the 911 platform (other than the Cup options), using a more powerful Turbo S engine. The GT3 RS uses a slightly tuned GT3 engine, a naturally aspirated 4.0L flat-6, also a monster on any track, but slightly slower than a GT2 RS overall due to the horsepower deficit. The GT4 RS is the Cayman’s track-focused model, using a detuned GT3 engine, but in a mid-engined layout. All are track-focused cars. 992 is just a Porsche internal designation for generation of 911. In this case, 992 is the newest and currently on sale version of the 911.

To your second question…the 992 is the current generation of 911. Originally, the 911 was a model number when it launched in '63. In 1989, the design was updated (significantly) and while the model name remained 911…the new internal model number was the 964. If you walked into a dealership in 1992 and bought a brand new, right in from the factory Porsche 911…you were buying a 911 (964). All of your paperwork and badging and whatever else would call it ‘911’ but when you’d bring it in the get service, they’d note that it was a 964. Then a few years later, another update happened and thus was borne the 993, and then year again a few years later the 996, and 997, the 991, and now…the 992. All of these are still called 911s…in the same way a C8 Corvette (the newest one) is called a Corvette the same as a C7 Corvette is…etc etc.

Sometimes, there’s incremental updates done within a given generation and this is designated with a .2 at the end. So if you bought a Porsche 911 in 2010…you were buying a 997.2. The big update that necessitated that change was the arrival of the PDK transmission to the 911 line, for instance.

911 = Model Name

992 = Model Number

Complicated? Yes. But it helps to make things easier to track for things like features, parts, etc. The actually year to year ‘updates’ aren’t very big (maybe a new color gets added, or new wheel options), but the bump up between generations is significant.

As for the GT4/3/2…think of them as ‘Fast, Faster, Fastest’ :P (respectively)

The GT4 is a NA Cayman, whereas the GT3 and GT2 (and their variants) are 911s. The GT3 is NA and the GT2 has a pair of turbochargers.

If it makes this easier, when there’s a GT”2” in the name, the 2 stands for 2 turbochargers.