As of now, Porsche's 911-range consists of no less than 16 different models - pretty impressive given the sports nature of the brand's most iconic car. And no, Porsche isn't done yet, with possible additions including the Speedster, GT2, GT3 RS, GTS and perhaps a model the name of which remains unknown – the convertible you see pictured in the following spy shots.

The soft-top model with the modified engine outlets and the centrally mounted twin exhaust systems was spotted testing amongst a group of facelifted 991-generation 911s.

From what we have heard, Porsche hasn't confirmed any plans for a convertible GTS, so unless it’s an early/unfinished prototype for the rumored 911 Speedster, one possible scenario is that the Germans may be working on a new and different version for the series. Thoughts?

Update: Our man on the ground told us the following: "I noticed that the air-intakes in the front bumper acted like curtains. They can be closed and opened depending on how much cooling is needed. When closed, they also help save fuel."

First production Porsche to come with such a system

A video demonstrating the Porsche 911 GT3's active rear-wheel steering system has been uploaded online.

The first production Porsche to come with an active rear-wheel steering system is the latest 911 GT3 and in this video we get the chance to see how it works. At speeds of up to 31 mph (50 km/h), the rear wheels will turn in the opposite direction of the front ones while after hitting 50 mph (80 km/h) the rear wheels are going to turn in the same direction to improve stability.

Porsche's engineers have installed two actuators which are in charge of steering the rear wheels up to 1.5 degrees.

As a reminder, motorization is provided by a six-cylinder 3.8-liter boxer engine developing 475 HP (349 kW) and 438 Nm (324 lb-ft) of torque sent to the rear wheels through a dual-clutch seven-speed gearbox and a locking differential. It will do 0-62 mph (0-100 km/h) in 3.5 seconds and can achieve a maximum speed of 195 mph (315 km/h).

Porsche is currently having some serious issues with the 911 GT3 as they have halted deliveries after five cars caught fire in recent months.

Tiff Needell reviews the Porsche 911 4S Targa, and finds out how well it matches up against previous 911 models.

The Targa has been part of the Porsche 911 family since 1965, but is relatively unloved. Can this new version change perceptions?

Out of all the Porsche 911 models, arguably the Targa is the most unloved. However, with the latest 991 model, Porsche has looked back to the 1965 original for inspiration.

Unlike the big sunroof on 993, 996 and 997 model Porsche 911 Targas, the latest incarnation has a stylish roll-over hoop and rear wrap-around windscreen like the original car which came out almost 50 years ago. Back then, though, you'd have to take the roof off yourself and find somewhere to store it.

Unsurprisingly, Porsche has found a slightly more modern solution for its £100,000 sports car, and it folds down nearly above the engine.

It's a good point to question where the Targa fits into the current 911 family, especially as there's already a Cabriolet version. However, it's around £600 cheaper than the soft-top, but £8,000 more expensive than the 911 Coupe. What's more, it's only available in 4 or 4S guise, meaning rear-wheel drive is out of the question.

The Porsche 911 Targa is 110kg heavier than the Coupe and 40kg more than the Cabriolet. The car we're testing, the 4 with a PDK SportChrono Plus gearbox, has a 0-62mph time of 4.8 seconds.

A minor criticism of the Porsche 911 Targa is that you can't get the roof down while on the move. What's more, given its 110kg extra over the Coupe, the handling has lost that final sharpness that you'd expect from a 911. However, Porsche knows this isn't the car that people who buy a performance orientated 911 will go for, so it's more of a comfortable relaxed cruiser.

The Porsche 911 Targa doesn't fill a gap in the range, it's more of a tradition for the brand but now, this is a tradition that works better than ever before.

The question is though, is is the Targa better than a Porsche 911 Cabriolet? The answer comes down to personal preference, but for what it's worth, which ever one you choose will guarantee you a great soft-top sports car.

All Porsche models will eventually be hybridized

A mysterious Porsche 911 prototype was spied testing on the Nürburgring and it could have been a hybrid version.

Get ready for yet another 911 (991) derivative as it seems Porsche is working on a hybrid version. Spotted here is a stock-looking prototype but upon closer inspection you can notice the back seat was removed in order to make room for what appears to be an electric motor and/or a battery pack. In addition, the vehicle sounds slightly different especially when shifting and accelerating.

This shouldn't come as a big surprise taking into account Porsche said last year that all of their new models will be offered with a hybrid system, including the mighty 911. Although this might upset purists, this decision is part of the company's objective to reduce fuel consumption and they have already done this with the Panamera S-E Hybrid.

Due to 911 GT3 engine reliability issues

A new report indicates Porsche is taking into consideration using a turbocharged engine for the upcoming 911 GT3 RS.

It is believed engineers at Porsche are worried about the reliability of the flat-six 3.8-liter engine installed in the plagued 911 GT3 which is why they are analyzing the prospects of mounting a turbocharged engine to squeeze the extra power the "RS" badge imposes.

This rumor makes sense taking into consideration Porsche CEO Matthias Müller said earlier this year the model could be delayed as a result of the fire-related call of the 911 GT3. However, adopting a turbocharged engine for the RS version could upset purists who prefer a naturally-aspirated motor.

In related news, the 911 GT3's four-wheel steering system will reportedly be offered on the Cayman, possibly for the range-topping GT4 version.

First there’s no manual transmission for the Porsche GT3 RS, and now it could be turbocharged?

Porsche is looking to turn away from tradition with its next 911 GT3 RS model with a turbocharged engine. Following the high-profile engine fire recall on the 991 generation GT3, Porsche is reportedly examining other, more reliable options to offer a more powerful engine for its even faster GT3 RS model.

As a result, a turbocharged powerplant is under consideration to help deliver the extra power needed without compromising reliability. The use of such an engine would also fit into the growing segment of supercars that employ turbochargers.

Additionally, the 911 GT3′s rear-wheel steering system is under consideration for the Cayman later in the model’s life cycle.