Modified my exhaust

Out came the angle grinder at the weekend, chopped off the blanking cap off my cans to perform the PSE hack. Cost me just a couple of quid for the stainless mandrel bends plus a pair of much bigger ovals. This is only a tempory mod as I am watching the pennies ... ok ok the truth, the Mrs has threatened to give me the boot if I spend anymore big bucks on the car before I finish off the bathroom and garden! Eventually I will get a Fabspeed, the company I work part time for is looking to become the UK importer so thought mine would make a great demo-car 8) I am also looking to fit twin rounds either side at the same time.

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PSE is the way to go, I done the hack originally to my originals and the difference was small. Must say, not a fan of the tips, they really don't suit the rear end, sorry. :what:

Nor me but they are better than the standard tiny ovals. I will be installing either the turbo style or 997 twin styles in the near future.

I was hoping to achieve an improvement over standard until I am allowed to spend on the car again. You are right, the increase wasn't worth the effort, anyone know to any other tempory budget mods I could do? I have found by doing a few searches that some have had good results from fitting & hacking 997 cans???

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I have a set of Turbo style tips if your interested. Used, but in good nick, polished nicely. Let me know, pm if you want can email pics next week when I'm back.

I did the Oettle style bypass on my 3.4 C2 and it worked really well. In my (and others) opinion it sounds brilliant. The "Mk 2" bypass that you have done only bypasses half the silencer, wheras the Oettle bypasses the whole system (albeit with a smaller tube). As for longevity of the Oettle system, I can't see any reason for it not to last, provided the right tube is used, and it is welded properly.

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I don't deny the silencers corrode and crack at the seam joints - all I'm saying that if properly executed, with the correct materials, then modifications should last for years. I think your post gave the impression they would likely fail quickly. Mine gave no signs of cracking or corroding after 3 1/2 years of use. The photo shows the original modification, and what I consider a proper TiG welded job.

Richard - would you be able to post the correct spec for doing this yourself? Then anyone doing DIY would know, and also anyone getting an indy to do it (me) would know what to expect them to do. I think in a previous thread you mentioned the tube should be 1" in diameter. What material should the tube be made from, and what welding process (sounds like TIG) and material should be used? Any tips on where to get the tube from? Thanks, Josh

Josh I used BS970 316S11 1" o/dia x 16swg wall tight mandrel bends and tube which I bought from a guy on eBay. This is often referred to as 316L stainless (American spec). Try a company called Dynoflow ( http://www.dynoflow.co.uk/ ). Yes, as I said, it was TIG welded. A friend of mine did the welding, as I'm not that proficient.

T316 is medical grade, pure stainless, the upside on this grade is acoustics but in such a small bore and length it would not make a difference, the downside is it is brittle so I would come down one grade to T304 and that way it would be more flexible. I totally agree with TiG welding, very neat and strong. The best and cheapest way to locate T316 is through dairy bend suppliers, this cuts out the middle man. I was buying big 4" bore T316 mandrel bends for under £10 so the ones needed for this job would be very cheap indeed. I am thinking of going one better and installing a QTP (quick time performance) valve at either end to make the noise switchable.