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Discussion Starter #1
have a question in theory since I am suffering from "myfundsarelow" I already have the 3" dp could I gut the stock cat and muffler and put them right back in? My exhaust measures 3-1/2 inches out side diameter. does 4" really make a difference?:dunno: Can you gut a muffler?
 

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On my truck before I had the stack on it, my brother cut the cat open and took everything outta it and then pounded a pipe through the muffler and welded it on there.
 

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Check your local laws and such, but chances are, you can just cut the stupic cat out all together. And as for the muffler, you might or might not be able to cut it out. (many states don't care at all)

The list of guys here, who have "straight piped" trucks, is very, very long.

As for going to a 4" exhaust, I noticed a difference on my truck. (and I've only got a downpipe back setup. The 4" exhaust just has more room, so a little less resistance. Plus, it helps lower the EGT's. But you don't "need" it by any means.

mike
 

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have a question in theory since I am suffering from "myfundsarelow" I already have the 3" dp could I gut the stock cat and muffler and put them right back in? My exhaust measures 3-1/2 inches out side diameter. does 4" really make a difference?:dunno: Can you gut a muffler?
There's people who make cat "test" or "delete" pipes, they go right in place of the cat.
 

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the cat is simple to gut just pull it out and pound somethin into it and dump out the chunks as you go. just make sure you get it all out cause itll rattle around if you dont. the muffler on my 97 was strait thru to begin with.
 

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Discussion Starter #7
after the down pipe is the muffler next in series then the resonator at the back wheels? also doesn't the cat get deleted on the stock downpipe with the 3" down pipe?
 

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not with all downpipes
 

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Discussion Starter #9
my buddy has a stock crimped down pipe and his looks like the cat is on there but my downpipe doesnt have the same. so i guess i just have to gut the muffler and resonator?
 

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im not sure what your calling a resonator, a stock exhaust gos downpipe, flange, cat, slip fit connection, muffler and pipe out the back
 

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Discussion Starter #11
not sure what the component is called but it is oval on edge first thing back from downpipe then a round component right before rear wheels
 

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oval thing after down pipe is the cat, and the can in front of the rear axle is the muffler.
 

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Discussion Starter #13
:woot: I have been trying to get this straight answer for some time. thanks Oasis.:thumb: guess there is nothing left to do but get to guttinn'
 

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Mine has been gutted and straight piped since mar 09. I cut the muffleer out and moved the 90 degree bend up to the cut so it dumps in front of the axle. I think I can see a little better throttle response and slightly better fuel mileage. But the best part is it sounds cool!!!! you can see the tip in this pic.

 

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Yep, definitley need to get them stupid cats outta the way. Like putting a tournakit on your exhaust. I went 4", I do have a muffler though, just to keep things on the legal side with moving and all. (different states, different rules). Once permenantly housed, the muffler's goin bye bye.

I tood a similar route, but I had my exhaust turned down, and it dumps right in front of the rear axle, but not on a tire. IDK about having the exhaust terminate right in front of a tire. As high as the EGT's can get, IDK if it would cause any tire issues or not. But to each their own.


mike
 

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heres what i just did


 

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looks good spanky
 

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sounds awesome too.:thumb::icon_ford:
 

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yea they sound really good straight piped, if your looking for somethign too piss you off on a saturday afternoon, look intop putting a 3 inch downpipe in, another weak link in the exhaust
 

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Discussion Starter #20
update:woot:

My neighbor and I set out to gut my cat this evening and see about muffler. We took the exhaust apart from the dp back and it turns out that the previous owner beat me to it!!!!! Cat totally gutted as well as the muffler. Thank you previous owner. This cold budweiser is for you:nod: How cool is that? I have to say that was a pain in the arse undoing everything but well worth our discovery.:clap:
 
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