Arrow R&D designed a full system, made with stainless steel collectors and 2:1 mid-pipe and a choice of different silencers, available in two different shapes (Race-Tech and Works) and in different materials. The silencers are street legal (tested under European Directive 97/24/EC, ch. 9), while a spare catalytic converter is available, to be used together with the silencers and collectors.  - 71429MI: stainless steel collectors, to be used with Arrow silencers. Kit is made with front and rear collectors and a 2:1 mid-pipe. Collectors are fitted to original headers.  - 71768PK: street legal Race-Tech silencer, with titanium body and carbon endcap.  - 71768MK: street legal Race-Tech silencer, with carbon fibre body and endcap.  - 71768AK: street legal Race-Tech silencer, with aluminium body and carbon endcap. - 71768AKN: street legal Race-Tech silencer, with black anodized aluminium body and carbon endcap.  - 71769PK: street legal Works silencer, with titanium body and carbon endcap.  - 11008KZ: catalytic converter kit.   All the silencers come with a removable dB-killer. Silencers are fixed to the frame by means of a stainless steel bracket. A metal plate is given to be fitted to exhaust valve actuator engine: the plate simulates the exhaust valve so to eliminate the warning message that appears when the exhaust valve is removed. Exhaust can give an extra power of around 6hp, depending on the silencer. Power increase starts to be noticeable from 3500rpm.