Because the GTS isn't already hardcore enough...

Guess who’s back? That’s right, the BMW M4 GTS is all set to return if these hot spy shots are any indication. Limited to only 700 cars, the most track-focused M4 of them all is likely getting a part deux, but it won’t be more of the same as it looks like some significant upgrades are in tow for the hardcore coupe.

BMW is dialing the aero package up a notch taking into account this prototype has a prominent front splitter, canards, beefier side skirts, and a reworked rear diffuser. That’s not all as the test vehicle is fitted with vented front fenders with massive air outlets behind the front wheels where it looks as if something is missing from the body.

Update:

2019 BMW M4 GTS spy photo
BMW M4 GTS

One would be tempted to say the prototype BMW is evaluating serves as a first sign of the long-awaited return of the CSL badge, which has been confirmed to make a comeback as a replacement for the GTS. That being said, it’s too early to know for sure as the M4 seen here could be called something else. Regardless of its moniker, it’s pretty obvious the Bavarians are working on a hardcore version as a last hurrah for the current-generation M4.

2019 BMW M4 GTS spy photo
BMW M4 GTS

We won’t be too surprised if the model in question will pack more punch than the M4 GTS, a special edition that ushered in BMW’s water injection system set to return in 2019. As a refresher, the “regular” M4 GTS offered 500 horsepower (368 kilowatts) and 442 pound-feet (600 Newton-meters) of torque and tipped the scales at 1,510 kilograms (3,329 pounds). Should the new version actually receive the CLS badge, it would have to be lighter than the GTS to live up to the “Coupe, Sport, Lightweight” name.

2019 BMW M4 GTS spy photo
BMW M4 GTS

Assuming it will have more power in a lighter package, the meaner BMW M4 will run to 62 mph (100 kph) quicker than the 3.8 seconds needed by the M4 GTS. The latter had an electronically governed top speed of 189.5 mph (305 kph), but it doesn’t necessarily mean a possible CSL will top that.

It remains a mystery at this point when BMW will introduce the more focused M4, although we will likely get to see it before the end of the decade.

Photos: Automedia, CarPix

2019 BMW M4 GTS spy photos