TVR Tuscan

De-Cat Pipes and Sports Exhaust Cans

The Tuscan S in particular will more than likely fail the MOT emissions test if decatted. The following is a modification guide submitted by Graham Hill, which provides a relatively quick change out between Cats and Cat bypass pipes.

Materials needed:

  • 1 set of good quality Cats (if removing originals be very careful and inspect condition of honeycomb strata you should be able to see light, clearly through the cat and nothing should be loose or rattling around inside).
  • 1 set of quality bypass pipes. (Note, in the pics they are shown ceramic coated. Graham had this done as extra).
  • 4 sets of slip ring pairs (note the Tuscan S pipes diameter is bigger than the standard 3.6 and 4 ltr. NOT all Red Rose cars had S pipes fitted. Check the diameter of your cat outlet pipes and purchase slip rings to suit). These can be obtained from almost any aftermarket exhaust fitting shop.
  • Molybdenum Disulphide or Copper slip grease.
  • A competent welder, the exhaust fitting shop you got the rings from will usually do it for a small fee.

Moding the Cats and Bypass Pipes

View pictureMark the Bypass pipes and the Cats in the same position and cut to provide a short stub section of exhaust pipe for each cat and each bypass pipe.

View pictureThe slip rings.

View picture View picture View picture Its important to separate the rings as male and female ends. Weld the male ring to the bypass pipes and the cats. The female ring to the cut stubs.

View picture View picture The Bypass pipe or Cat together with the stub (slip ring mates nicely).

View pictureThe slip ring locking collar shown as fitted and nipped up. Graham used copper slip grease between the joints of the slip ring.

View picture View picture This shows the Bypass pipes fitted awaiting the fit up of the rest of the exhaust system.

View pictureExhaust pipes fitted.



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