Catalytic Converter (CAT) (Manifold & exhaust systems)

Catalytic Converter (CAT)

The CAT is mounted between the downpipe and the centre pipe. A flange is welded to each end of the CAT with three captive bolts in each flange. The CAT connects to mating flanges on the downpipe and centre pipe and is secured with nuts. Metal gaskets seal each flanged joint.

NOTE: Refer to the Emissions section for a description and operation of the catalytic converter.

CAUTION: Leaks in the exhaust system can damage the catalyst by drawing oxygen into the exhaust system which causes the catalyst to overheat. Engine misfires cause overheating of the catalyst which may lead to irreparable damage.

Intermediate Pipe Assembly

The centre pipe has a flange at its forward end which connects to the catalytic converter flange, secured with three nuts and sealed with a metal gasket. The rear of the centre pipe shaped to go around and over the rear subframe. The centre pipe is supported at the flanged end to the body via a mounting rubber.

Tailpipe Assembly

The tailpipe assembly is of fabricated and welded construction and comprises a large capacity silencer, a connecting pipe and a tail pipe. The curved connecting pipe is welded to the left hand end of the silencer and connects with the rear pipe section of the centre silencer assembly. The tail pipe is welded to the right hand end of the silencer and directs exhaust emissions downwards from the right hand end of the rear bumper.

The connecting pipe is a sliding fit on the centre pipe. A clamp secures the two pipes together. Attachment bars are welded to each end of the tailpipe assembly and provide attachment points for the tailpipe to the body via mounting rubbers.

The tail pipe silencer is fabricated from a 0.6 mm mild steel outer cover with a 0.5 mm stainless steel inner liner and is oval in section. An end plate is secured to each end of the outer cover with seam joints. The inlet and outlet of the silencer are diametrically opposed at each end of the silencer. The inlet and outlet each incorporate a perforated baffle tube welded to each end plate and retained internally by two baffle plates.

A perforated balance pipe is located between the two baffle plates and exhaust gases from the inlet is forced to flow through the balance pipes before it reaches the outlet. Two open spaces at each end of the silencer act as expansion chambers to further reduce engine exhaust noise.

The upper surface on the outside diameter of the silencer has an additional plate welded, with an air gap between the plate and the silencer body. The air gap is filled with a heat absorbing ’Fibrax’ insulating pad which reduces heat from the silencer radiating to the floorpan of the vehicle.