Stock Muffler Cut Open

[EAGLE5]

Yeah, none of this is about the money. It's just fun. Also an excuse to learn to weld. I think i'll start by trying to remove the baffles as much as possible.

Originally Posted by mad_sb

would be louder due to less resistance on the path to exit but that should also mean a little more power. Ultimately i am after the best flowing quiet exhaust i can get. If you have to spend more than a 100 bucks on material and labor it gets to the point that an aftermarket unit is more attractive.

For best flow you would probably need to gut the interior and weld in a perforated y pipe to connect the inlet and outlets then pack the core with steel wool / muffler packing material.

[Captain Insano]

This makes me wonder what aftermarket suitcase exhausts look like inside. I would have never pictured that inside the OEM exhaust muffler. I would have thought those pipes at least connect or at a minimum have flow moving from outlet of the inbound pipe in a straight path (maybe not piping) to the outbound pipe. And that is nothing of the sort in the OEM muffler. Seems like that would flow really bad. So again, I'm surprised as alot of aftermarket tuners have stated the OEM catback "isn't that bad" and that is not much of a "power adder" modification and more of a sound modification.

[jflogerzi]

Originally Posted by Captain Insano

This makes me wonder what aftermarket suitcase exhausts look like inside. I would have never pictured that inside the OEM exhaust muffler. I would have thought those pipes at least connect or at a minimum have flow moving from outlet of the inbound pipe in a straight path (maybe not piping) to the outbound pipe. And that is nothing of the sort in the OEM muffler. Seems like that would flow really bad. So again, I'm surprised as alot of aftermarket tuners have stated the OEM catback "isn't that bad" and that is not much of a "power adder" modification and more of a sound modification.

in reality they right as most after market exhausts only add 5-10HP at peak, but thats it. I bought mine purely for sound.

[mrk1]

Awesome! opening/altering mine is a rainy day project Ive had for a while.

Im thinking altering to accept a 2.5" mid pipe and re route to make straighter design.

[EAGLE5]

I wouldn't expect any power from an exhaust. It's pretty darn big and open for a 2-liter engine. With a turbo, that's a different story. Then you probably want to go 3" all the way, and even bigger if you're going for big power. I'm just playing for sound's sake.

Originally Posted by Captain Insano

This makes me wonder what aftermarket suitcase exhausts look like inside. I would have never pictured that inside the OEM exhaust muffler. I would have thought those pipes at least connect or at a minimum have flow moving from outlet of the inbound pipe in a straight path (maybe not piping) to the outbound pipe. And that is nothing of the sort in the OEM muffler. Seems like that would flow really bad. So again, I'm surprised as alot of aftermarket tuners have stated the OEM catback "isn't that bad" and that is not much of a "power adder" modification and more of a sound modification.

[Captain Insano]

Yep, I get what you guys are saying and aftermarket catback results aren't much higher than stock so I get why the tuners say that too.

I'm just very surprised the inside looks like that after buying exhaust mufflers for previous sports cars with inner piping and perforations in the central pipe with fiberglass or steel mesh outside the perforated piping.

[EAGLE5]

Wow. Totally thought this would get more interest.

[Kodename47]

So how would you improve on the original design? Weld the pipes straight through?

[EAGLE5]

Originally Posted by Kodename47

So how would you improve on the original design? Weld the pipes straight through?

Not sure exactly. Remove the baffle walls. Perhaps cut off the perforated sections then weld on bellmouths. I've no idea how loud it is without the muffler. Any videos somewhere?

[86_ZN6]

we used to do this at the shop.

altering the inside did not show an increase in performance.

only sound

[EAGLE5]

Originally Posted by 86_ZN6

we used to do this at the shop.

altering the inside did not show an increase in performance.

only sound

Yep. I think that's the goal. I think it would have to be forced induction to see a performance benefit after mods, and even then it'd probably need a tune to see it.

[RhetoricalGambit]

Originally Posted by jsimon7777

Yep. I think that's the goal. I think it would have to be forced induction to see a performance benefit after mods, and even then it'd probably need a tune to see it.

So what was the out come of this?

[Basket Case]

Originally Posted by mad_sb

Without getting a better look, my first attempt at modding would be to cut out the pipe sections in yellow, then pack the areas in blue with muffler packing material.

That would probably be a good place to start. I am curious though with the addition of a packing material if it wouldn't make it just as quite as stock.

[EAGLE5]

Now that I'm not working every single Sunday and a major home project is coming together, I'm getting closer to restarting the experiment. Oddly enough, I now own three stock exhausts. I might cut open and modify a second one after I play with this first one. For this one, I'm just going to cut out some piping and baffling and see if it doesn't drone. I finally did find the sheet metal cutting tools I had misplaced.