The standard exhaust on the MGF and MG TF is suspended on rubber mounting rubbers, one at the downpipe and a pair at the silencer, which isolate the system from the bodyshell and absorb vibration. Rubber does this job well when new, but it sits directly in the path of exhaust heat and the elements, and over time it perishes, softens and tears, allowing the system to sag or knock against the underbody. Polyurethane mountings are offered as a longer-lasting alternative. The material resists heat and oil far better than natural rubber, holds its shape under load, and locates the exhaust more positively, which is particularly welcome on a mid-engined car where the system is tucked up behind the cabin and any movement is quickly felt and heard.
What the Upgrade Covers
In place of the original silencer mounting rubbers and downpipe mounting rubber, the polyurethane set provides equivalent hangers in the harder-wearing material, typically supplied with the fixings needed to fit them. They are a direct replacement that uses the existing mounting points, so no modification to the body or exhaust is required. Because they are firmer than standard rubber, a small increase in transmitted vibration at idle is normal and is the trade-off for the improved durability and location. The mountings suit both MGF and MG TF systems and are a natural companion to a stainless steel exhaust upgrade, where it makes little sense to hang a lifetime-guaranteed system on perishable original rubbers.
Fitting and Ordering
Polyurethane exhaust mountings are a straightforward fit for the home mechanic, best tackled with the system cold and adequately supported. They are commonly fitted at the same time as a new or stainless exhaust, or when renewing a tired system's hangers in isolation.
When ordering, consider whether the downpipe mounting, the silencer mountings, or the full set is required, and whether an associated stainless fitting kit is wanted to complete the installation with corrosion-resistant fasteners. Renewing all the mountings together gives the most consistent result and avoids leaving an old, soft rubber working alongside new firm ones.