No CATS, No Muffler, Dump at the Y – How Loud?

[chris070780]

First let me state that my 91 X is pretty much just a beater off-road truck. I just drive it to and from the trails. I am in the process of putting my tranny back in after changing front trans seal. I cut the exhaust off right after the O2 sensor. Being that this is an off road truck I am not inclined to put the muffler back on. It looks like because the Y section is oval shape and it might be hard for a shop 2 reconnect??

Anyone run the X this way? Is it ridiculously loud? I haven’t had a chance to start it as the tranny is out. I just want to weight my options now.

 

[SuRrEaLNJ]

it will be rediculously loud. like i hope your gonna trailer it to and from the trails loud

 

[rileyrs]

its loud, thats for sure, but if it only ever sees the trails then it might not be too bad

 

[chris070780]

Any have any experiance welding pipe up to the that oval pipe right before the cat?

 

[ViperPliskin]

Loud?

When I rebuilt my 5.0 I started it with only the headers attached. I was surprised it wasn't louder. My whiney neighbors didn't even complain.

 

[Carguy3J]

Cutting your exhaust that short can also affect how it runs, and not in a good way. Having and exhaust path that short severely reduces scavenging effects, and could even introduce reversion (negative/reverse flow) between exhaust pulses. On top of that, all that exhaust is building up under the cab. You'll be breathing in a ton of carbon monoxide, even more so one moving slowly on a trail.
Any exhaust should always end at least past the driver, and preferably as far back as possible, such that the exhaust gases exit the tailpipe outside the body. At least run straight pipe, but I would suggest a high-flow muffler, if you want to be able to have functioning ears down the road. What sounds "ok" at idle, si going to be ridiculously loud under load.

 

[Tony H]

I have welded exhaust before. I wouldn't Butt weld it unless you can slip another Pipe over it and weld it too.

It'll be loud, combine that with the ugly sound of a 6 cylinder and...yuck

 

[rhauf]

its going to be loud, sound like crap, and you're going to smell exhaust inside the truck a ton since it's dumping so close to the front of the vehicle.

 

[94Sport5Sp]

Hi:

How do you know you will not drop hot embers on the trail? With a short pipe there is not much time and if something hot hits dry grass you could have more than noise.

Just a thought
PaMnd

 

[little x]

It will be loud and have no torque or power. I have a cat delete pipe for sale, if your interested pm me. Just bolt it up to the y-pipe and run whatever you want behind it, straight pipe or a muffler.

 

[Anime]

As already mentioned, the loudness isn't really the issue (although the 4.0 OHV can sound pretty mean at high revs with some mods), but you'll have some running issues.

Personally I'd say put at least the factory cats back on, then run a short 2.25-2.5" pipe from the cats, back to either a dump, or even better, a pipe that turns and exits in front of the rear tire. You'll keep the power and torque, the engine will run good, and you won't be choking yourself or others with toxic fumes.

You can have a pipe enlarged at one end in an oval shape, or have two pipes welded to make the oval shape of the Y-pipe. I'd still say not to delete the cats, but you can use this method to run a single high-flow cat if you're so inclined.