Milltek’s M135i (F20) performance exhaust system

Milltek has released details of its new performance exhaust system for the new BMW M135i. The latest F20 chassis car features BMW’s twin scroll turbo engine, which Milltek says suits its extraction technology and craftsmanship. Initially launched as a cat-back only set-up, Milltek will provide the additional option of a turbo-back system, complete with large bore downpipe and high-flow cat configurations.

The exhaust features a dual outlet, with options of polished or black GT-90 trims. The cat back system is fully EC-approved and offers an insurance and warranty friendly tuning solution.

When designing the system, Milltek says its engineers reduced marginally the OEM’s systems 80mm diameter down to 76mm, somewhat unusually. The Derbyshire manufacturer explains that this was because the factory system is actually squashed in a number of places to allow clearance for underbody components, whereas the 76mm design can run unfettered from front to back, improving gas-speeds – and therefore performance – overall.

As usual, Milltek has fabricated the entire system in its Ilkeston factory from 304-grade non-magnetic stainless steel for improved durability and effectiveness. Sound-wise, the system is tuned to give a powerful growl under heavy throttle loads, but factory-esque noise levels under cruising and town driving.