How to make and fit your own cat bypass on a 944

The de cat on my red S2 was a lot of money, so i thought i’d make and fit a straight through pipe in place of the cat on my cab. my biggest problem was getting the car high enough to drop the exhaust. i have since found a method of getting the car really high, without axle stands.

But thats for later, on this job low axle stands were used.

I removed the whole exhaust including the exhaust manifolds, once off, i cut out the cat.

Easy! i found a company on ebay that will supply the length you want, and swage the ends so they fit over your old exhaust ppes.

Dont forget to add about 2 inches each end to slot the new pipe over the original.

I also decided to do away with the small second silencer and make the join just before the rear axle beam.

The photos show the process step by step, i guess my total cost was under £30.

Noise wise it is nowhere near as loud as i expected! in fact not much difference, i think it picks up a little quicker but that could be just my imagination. a trip to santa pod will show if there is any real improvement.

The only problem is how close the pipe gets to the rear brace and cross beam.

Mine rattled when i first fitted it but i have now modified the alloy cross member and center of the beam with a angle grinder.

Now no rattles and i do not this small mod weakens the bracket at all. many years of shaving weight of race motorcycles behind me!

exhaust off and cat cut off
good reason to dump the catalytic converter
just kept the one back box
cross brace modified
modified cross brace and beam
stuart

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