Bull-X Tronic control unit (with ECE type approval)- Audi RS4/RS5 B9 (HGBXTSET-8)

With ECE operating licence*: *Only applies to the following selection in the “Operating mode” field: Bull-X Tronic control unit (with ECE operating licence). This valved exhaust system has ECE approval, so it can be used on the road without being entered in your vehicle documents. Caution: exhaust systems with ECE are not affected by the “valve ban” and may continue to be used completely legally on the road. While driving you can decide whether you want to drive in comfort or sport mode. If your vehicle has a drive profile selection, it can be controlled via that. For vehicles without drive profile selection, control can be via a supplied button. The button’s LED lighting tells you whether the valve is currently open (light off) or closed (light on). The control unit automatically closes the valve in all ranges required by the ECE regulation, regardless of which mode you are driving in. In general, the Bull-X Tronic offers two control options: - Sport (Dynamic, Race): the valve is controlled within the approved limits of the ECE regulation. - Comfort mode: the valve is always closed, but opens while driving within the approved limits of the ECE regulation from 75% throttle opening. You can find more information in our info video.

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