Originally Posted by GotaNeed4Speed6
well i just bought a new muffler for my 1997 integra gs, and i just have the muffler. And i was looking at it i noticed that my OEM muffler has a bent tube conecting the muffler to another tube. I belive that the bent tube is called a mandrel bent tube, correct me if i am wrong. And i was wondering if the best idea to put on the new muffler is to cut the mandrel bent tube, or get a new mandrel bent all together.. PLEASE HELP!
Thank you
If all you're doing is replacing the rear muffler, I'd just buy a coupling from your local auto parts store and use it to join the old tubing to the new muffler.
Trying to find a replacement tube won't be easy, and unless the original tubing is severely rusted, there's no real advantage to replacing the stock tubing.
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There is one correction to make: "Mandrel-bent" tubing refers to the
method by which tubing is bent, not the shape of the tubing in general.
Mandrel-bending requires the use of hardened steel forms called mandrels, which maintain a constant internal diameter throughout the bend. It's a slower, more costly method of bending tubing; most OEM car manufacturers do not use this method for fabricating their exhaust systms.
Instead, most OEMs use crush-bent tubing. The tubing is heated and set in a clamping rig that quickly produces segmented curves by rapidly bending the tubing without the use of mandrel forms. These bends are visible from the outdside by a series of ridges that are a by-product of uneven wall thickness. Internally, the diameter of the pipe is not constant; the tighter the bend, the narrower the internal diameter. Gas flow suffers as a result of the decrease in diameter.