It is positioned between the most powerful BMW series production models and thoroughbred BMW M vehicles. BMW M Performance power units generally boast a noticeably higher performance than the previously most powerful engines of any BMW series and have M-specific characteristics in terms of suspension setting and visual appearance, though without any limitations in terms of suitability for everyday use.
Heart of the new BMW M135i is the straight six-cylinder petrol engine with Twin Scroll Turbo technology, Valvetronic, Double VANOS and High Precision Injection. It delivers 235 kW/320 hp and a maximum torque of 450 Nm, power transfer being effected by the six-speed manual transmission fitted as standard.
The BMW M135i sprints from 0 to 100 km/h in just 5.1 seconds (automatic: 4.9 seconds) and reaches a top speed of 250 km/h – the top limit permitted by the vehicle's electronic speed control system.
Average fuel consumption in the EU test cycle is 8.0 litres (7.5 litres)/100 km, and the CO2 emissions level is 188 grams (175 grams) per kilometre. The exclusive power train for the compact BMW M Performance car also features a customised cooling system, M performance control and engine sound tuning, plus a newly developed six-speed manual transmission with dry sump lubrication. A dynamic eight-speed automatic sports transmission with gearshift paddles integrated in the steering wheel is available as an option.
The performance potential of the BMW M135i is reflected in its individual exterior and interior design features. The front apron is typical of M styling that reflects the car's firm and responsive road handling, with the large air intake vents needed to meet the cooling demands of a high-performance straight six-cylinder engine, auxiliary units and oversized brakes. The competitive character of the car can also be seen in the three-dimensional flaps on the outer air vents, a detail inspired by automobile racing. These air inlets take up the space reserved for the fog lights in the other versions of the three-door BMW 1 Series. They are separated by horizontal struts in Ferric Grey metallic – a design detail that distinguishes BMW M Performance cars.
In addition to the BMW Individual high-gloss Shadow Line and the exterior mirror caps in Ferric Grey, the specially contoured side skirts and 18-inch M light alloy double-spoke wheels with mixed tyres intensify the side profile of the BMW M135i. The rear apron, the lower portion of which is finished in Dark Shadow metallic, also encloses the dual exhaust pipes.
Furthermore, the door sill finishers with aluminium inserts that feature “M135i” lettering match an interior design that expresses the joy of sheer driving pleasure. The interior details include exclusive cloth Hexagon/Alcantara upholstery, an M leather steering wheel with multifunction buttons and blue accent stitching, the BMW Individual roofliner in Anthracite, interior trim in Aluminium Hexagon with matt Estoril Blue or high-gloss black accent lines, gear selector and handbrake with leather gaiters, M driver footrest, speedometer and rev counter with red chronoscales. The colour of the interior lighting is variable, and the car key features blue detailing.