The new BMW M3 is the gift that keeps on giving right now. Just last week, we caught BMW testing the next-generation M3 and M4 at the same time, allowing us to see how they compare. Since then, BMW's M3 pre-production prototype has started strip teasing as the much-anticipated next-gen performance sedan approaches its launch date.

This time, our spies have spotted a trio of BMW M3 prototypes parked next to each other at a BMW test center. Whereas previous prototypes were fully camouflaged, the side profile is now almost fully visible, giving us a more revealing look at the pre-production body in several different colors.

At the front, the controversial new kidney grille is exposed in all its gaping glory. Noticeably, the air intakes on the front bumper of the silver and black M3 prototypes look different to the red one, which has honeycomb grilles in the air intakes on the left and right side. At the back, the diffuser also has more fins on the silver and black models.

This suggests the silver and black prototypes are M3 Competition models, while the red one is most likely a regular M3. The wheels also appear to be production-ready, as are the headlights and taillights.

While we'll have to wait until September for the covers to come off the new M3, BMW has already revealed some of the technical details. Under the hood, the new BMW M3 will be powered by the same twin-turbocharged 3.0-liter straight-six engine as the BMW X3 M and X4 M, which will offer huge performance gains over the outgoing model.

This unit will produce 480 hp in the standard M3, which will be sent to the rear wheels through a six-speed manual transmission. If that's not enough grunt for you, the output will increase to 510 hp in the new M3 Competition, which will only be offered with an eight-speed automatic transmission. It will also be offered with AWD after launch.