It's where you basically install a Y pipe somewhere in the exhaust. One branch runs to your normal exhaust, the other branch has 3 options:
-bolt on a block off plate that you can later remove / install
-bolt on a mechanical valve (looks like a throttle body, has a cable you run into the cabin)
-bolt on an electric valve (looks like an electronic TB). Lets you open and close the exhaust dump in seconds from a switch in the cabin.

The upside to a cutout is you can basically have 2 different exhausts on the car at once. At the most extreme, you can go from totally dumped exhaust to stock exhaust with the flip of a switch.


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Yesterday I jacked up the car to take a look at the exhaust system. There's already a y pipe that goes from the resonator and splits off to the two mufflers. How would you suggest going about a cutout with that info? Also, is there anything I need to be concerned about when dropping the catback, and testing the sound, like the hot fumes damaging something else under the car?

 

That engine won't really sound great no matter what you do. The setup i have is stupid loud, drones like crazy and everything vibrates in the car. Just a heads up.

 

Depends how much of the system you would want to bypass. I'd imagine the easiest place for a diy install would be to replace the resonator with am aftermarket Y for a cutout as that would give you a nice big open section to put it in.

It's far easier if you're able to weld. You can literally cut a hole almost anywhere and just weld a flange on - after the resonator, before the resonator, before the cat, etc. Personally, the one on my monte is right at the base of the firewall on the downpipe. Right where it turns from coming down the firewall to head back, I've got a flange straight on the bottom with a cutout. On my Grand Prix I ran the Y with a cutout in place of the stock resonator.


The outlet will be pretty far from everything other than the floor board, but I woudnt go on a road trip like that or anything. Just taking it for a spin around the block isn't going to hurt anything. People have done this for drag strip runs. If you did want to run it long term, you could always just stick on a turndown.

My bet is that you're not going to last long enough to have to worry about anything getting heated up anyways, lol. I give you about 2 minutes before you're headed back to the garage dying to bolt the exhaust back on.

 

Nothing to worry about with heat under there..

Just throwing that out there for ya..

 

The only open part of the exhaust system is from the y pipe to the mufflers. The cat and resonator are right inside a channel built for them, then the pipe going to the y is also in a channel on the passenger side of the car. And I just want to try something different with the exhaust, because currently, I can't even hear it over the engine noise.

 

Thats what I mean though, if you're set on doing it DIY and having to clamp stuff on, it limits where you can put one. With a welder the options are endless. You can add a flange just about anywhere then.

If you're just looking to make it a bit louder, have you thought about just doing a muffler swap?

 

I'll do some research on the cutout later.
​​​​​​​Originally, that's what I had in mind. But after listening to sound clips, it seemed like I would have to do more than just the mufflers to get the sound I wanted.

 

I wanna say the best 3800 I ever heard was when I had a thrush welded muffler connected right to the downpipe and nothing after that..

It was insanely loud, unbearable drone inside, and I got pulled over a couple times but BOY did it sound awesome from the outside.. Idle, cruise, and WOT..

I know, its a little late in the thread to say this but with all the other info youre getting its just another piece to add..

 

I ended up dropping the catback yesterday (Monday), and I had lots of fun with it. Granted, the sound isn't the best because of the engine and what not, but it's what I've got, and I really like it. The startup sounds great, and gave it the rumble that I wanted. There is a lot of vibration currently, because the exhaust is letting out in the middle of the car, rather than it's intended place at the back. But the way you guys have been talking about how bad the drone is, I was expecting it to be much worse than it was. I drive with the windows down (it's already hotter than hell here in Texas, and the AC in my Monte doesn't work), and the exhaust is getting let out right about even with the windows. Despite that, it wasn't so bad. Once I put pipe in, the sound will be further away, and easier to bare. And when I get the AC fixed and I'm able to drive with the windows up, it'll be even quieter to a passenger who might not like the noise as much as I do. I would like to note that I haven't driven it at highway speeds yet, but I hardly ever do any highway driving anyway.