Exhaust systems on the MG ZR, ZS and ZT are model and engine specific from manifold to tailpipe. Although the cars share their bodyshells with the donor Rover 25, 45 and 75, the MG-specific suspension geometry, sports tuning and (on the ZS and ZT) the larger silencer and tailpipe profile mean that very few exhaust components are directly interchangeable with the Rover equivalents. Within the MG range, each engine variant has its own exhaust calibration: K-series 1.4, 1.6, 1.8 non-VVC and 1.8 VVC each take a different system; the 1.8 K-turbo on the ZT 160 has its own turbo-back arrangement; the KV6 takes a twin-downpipe system serving both cylinder banks; the L-series and M47R diesels each have their own intercooled, single-pipe layouts; and the ZT 260 V8 has a fundamentally different system that shares no parts with any FWD ZT. Engine number prefix, model and (on facelift cars) the January 2004 specification breakpoint should all be confirmed before ordering centre or rear silencers, catalytic converters or downpipes.
K-Series and KV6 Exhausts (ZR, ZS and FWD ZT)
K-series ZR and ZS cars use a single-downpipe system with a primary catalytic converter close-coupled to the manifold for emissions performance, a centre silencer, and a rear silencer with a single tailpipe (the ZR 160 was supplied with a single oval tailpipe as standard, with twin-tailpipe styling reserved for the ZS 180 and for aftermarket sports systems). System diameters and silencer internals are tuned to the engine variant, so a 1.4 ZR 105 system is not the same as a 1.6 ZR 120 or a 1.8 VVC ZR 160 system, even where the centre section may look superficially similar. KV6-engined ZS 180 and ZT 160/180/190 cars use a twin-downpipe system serving both cylinder banks, joining into a Y-piece ahead of the centre section, then continuing to a single rear silencer with twin-tailpipe finishers. The 1.8 K-turbo introduced on the ZT 160 from mid-2003 has its own turbo-back specification and is not interchangeable with the earlier KV6-engined ZT 160 system.
T304 stainless steel performance systems are widely available from specialist suppliers and offer corrosion resistance and a modest power gain over the original mild-steel aluminised system, while remaining a direct fit to OE mountings.
L-Series and M47R CDTi Diesel Exhausts
The L-series 2.0 turbodiesel ZR TD and ZS TD use a single-downpipe system with an oxidation catalytic converter sized to the diesel exhaust temperature window, a centre silencer matched to the lower-frequency exhaust pulses of the diesel four, and a single-tailpipe rear silencer. The system is shared with the Rover 25 and 45 L-series cars but with MG-specific rear silencer styling. The BMW M47R CDTi in the ZT uses a different layout reflecting the common-rail diesel's higher exhaust gas flow and the transverse engine installation: a single downpipe from the Mitsubishi turbocharger feeds an oxidation catalyst, then runs to centre and rear silencers tuned for the saloon and ZT-T estate body styles.
Pre-2002 cars without the intercooler (badged CDT rather than CDTi) have a different downpipe routing from the 2002-onwards intercooled CDTi specification, an important breakpoint when ordering downpipes or front catalysts. Diesel-spec rear silencers are not interchangeable between L-series and M47R cars.
The ZT 260 V8 Twin-Bank Quad-Tailpipe System
The ZT 260 saloon and ZT-T 260 estate use a bespoke exhaust system designed specifically for the longitudinally mounted Ford Modular V8 and rear-wheel-drive layout. Each cylinder bank has its own downpipe and primary catalytic converter, and the two systems run twinned along the length of the car beneath the redesigned transmission tunnel and rear suspension subframe. A short crossover balance pipe joins the two systems above the rear axle to even out flow between the banks. Rearward of that, each side terminates in a discrete rear silencer, and each rear silencer feeds a pair of tailpipes, giving the ZT 260 its signature quad-tailpipe rear view.
The system is the principal external identifier of a ZT 260 against the FWD ZT range, the quad pipes and the model badging are the only obvious visual differentiators. Standard rear silencers are mild-steel aluminised and are the commonest wear item on the system; T304 stainless replacement boxes are now produced specifically for the ZT 260 and the post-facelift Rover 75 V8 to address the original material limitation while retaining the OE quad-tailpipe appearance. Approximately 883 V8 cars were produced in total across saloon, estate and the post-facelift Rover 75 V8 sister model, so any ZT 260 exhaust components are intrinsically rarer than FWD ZT parts.