Based on the shared platform of the 1-series, Milltek Sport’s R&D team was able to carry over much of the development work it did during 2014 on the M135i model. Therefore, the new M235i system uses the existing and well-proven EC-approved cat back system from the M135i, but with the added optional feature of a new race-spec hi-flow Sports Catalyst that features Milltek’s latest Active Valve technology, utilising OE-spec BMW electronic valves in its construction.
These intelligent new valves have been designed to seamlessly integrate with the car’s central electronics, enabling a more sporty and aggressive tone when either “Sport” or “Sport Plus” modes are selected, but when the vehicle is left in “Comfort” or “Eco Pro” modes, a more subtle and OEM-style note is produced, making for sophisticated and refined cruising comfort, even at high speed.
As the M235i uses a later-spec turbo than the earlier M135i, Milltek has also revisited the design of the downpipe, in order to maximise flow and increase performance. The new part as available either with or without the HJS high-flow sports catalyst, depending on the customer’s application. With the cat fitted, full emission legality can be achieved. Speaking of which, Milltek also has a fully EC-approved version of the downpipe/catalyst in development, which will appease even the most ardent of testing bodies.
The new system has been designed around carefully optimised 76mm (3”) non-magnetic stainless-steel pipework which, in testing, offered the best balance between flow and back pressure for the sharpest throttle response. Tips wise, the tastefully-styled GT90s perfectly fill the M235i’s rear valance and are available in either polished or Cerakote black finishes.
Available now from a Milltek Sport stockist near you.