Custom Exhaust - Need Advice

[pezzonovante88]

I am having my catalytic converter and muffler removed and am replacing them with some straight 2" piping with long resonated tips on the end. Will there be any back-pressure problems with a setup like this, or any other problems I may be overlooking? The car in the first two pics sounds great IMO, but he still has the Cat, whereas mine is being removed.
Attached are a few pics describing what I'm doing:

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(First two pics are courtesy of Martin P. from Montreal)

[vwdmc16]

Ive seen a D with a mufflerless set up like that, man that was too loud for any length of a drive, Why do you want it so loud?


As for your question, just the legality of it is in question, with that much tubing you shouldnt have issues of the exhaust valves burning but still just shear noise.

[Nicholas R]

I dont think there should be any problem. The need for back pressure is a common misunderstanding. People often think their exhaust needs a certain back pressure, when truly it needs a certain flow and velocity. The point of an exhaust system after all is to get rid of the exhaust. The balance you need to find is not in the pressure but in the flow. Yes the pipes need pressure to flow but that doesn't mean it HAS to be restricted by a muffler. Flow is more affected by exhaust pipe size and routing than anything. The only engines that actually NEED back pressure are 2 cycle engines because it helps keep new fuel from escaping the cylinder.

You should be fine. But it is going to be loud as hell when accelerating, especially without anything to dampen the pops when your RPM's quickly drop. Who knows though, it may sound awesome! I took the mufflers off my car this weekend to start figuring out my new exhaust plan. I drove it around a little too. I LOVE the way it sounds... but I honestly felt bad driving around town. It's definitely not something I could do full time.

If you do it post a vid. I'm curious to hear how it sounds!

[stevedmc]

There is plenty of room for a muffler (and a catalytic converter) straight out the back of the car:

http://sphotos-a.xx.fbcdn.net/hphotos-ash4/311425_276395649072359_499366569_n.jpg

It will look unbalanced without one on the other side too:

http://sphotos-a.xx.fbcdn.net/hphotos-ash4/388606_276418859070038_1256165580_n.jpg

[pezzonovante88]

Ive seen a D with a mufflerless set up like that, man that was too loud for any length of a drive, Why do you want it so loud?


As for your question, just the legality of it is in question, with that much tubing you shouldnt have issues of the exhaust valves burning but still just shear noise.

Interestingly, the one I heard with the heavily packed exhaust tips wasn't that loud. I mean, clearly it wasn't exactly quiet, but it was not obnoxious. Although, if there's room, I might have them install a little resonator where the cat was just to take the edge off.

[dmcjohn]

On my car I'm planning the exhaust route to be similar to Steve's above, except using smaller mufflers on each side, as per pictures attached. It's probably going to be very loud but on my car the engine sits a few inches further back, so there is no room for a large muffler between the engine and fascia as in stock DMC's.

It's a 2.5 inch diameter - comes with separate exhaust tips as shown so I can cut them to suit once the mufflers are in place. All the pieces are SS304.

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