Gutting 2nd cat
06-09-2016, 02:05 PM
#1
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Gutting 2nd cat
Before everyone jumps on me and says click the search button that option does not work well at all on my phone. With that being said has anyone gutted their second catalytic converter and left the stock muffler? If so can someone please post a video or sound clip please? I cannot find an aftermarket muffler that I like the sound and everyone keeps telling me to just gut the converter to make it louder and free up horsepower. I'm just curious as to what it would sound like. Thanks in advance
06-09-2016, 02:11 PM
#2
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I don't know why the search would be different on a phone. But, here is a lengthy discussion.
https://www.chevyhhr.net/forums/hhr-...2nd-cat-49887/
https://www.chevyhhr.net/forums/hhr-...2nd-cat-49887/
06-09-2016, 04:58 PM
#3
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06-11-2016, 06:42 AM
#5
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Before everyone jumps on me and says click the search button that option does not work well at all on my phone. With that being said has anyone gutted their second catalytic converter and left the stock muffler? If so can someone please post a video or sound clip please? I cannot find an aftermarket muffler that I like the sound and everyone keeps telling me to just gut the converter to make it louder and free up horsepower. I'm just curious as to what it would sound like. Thanks in advance
The 1st & or the 2nd cat could be restrictive on a 2.2/2.4 HHR.
Maybe a larger diameter aftermarket DP might be the way to go, I really don't know...
Do a search on exhaust mods for the 2.2/2.4 engine.
Last edited by 2005HHRauto; 06-11-2016 at 07:20 AM.
06-11-2016, 08:07 AM
#6
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Location: Stevens Point, WI
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Of all the catalytic converters I've gutted (3 or 4 I guess) I've never left anything inside when I'm done. I used a solid steel rod that was maybe an inch or so in diameter and a B.F.H. (Big ___ Hammer) You just get the cat on the floor, stick the steel rod into the inlet and start hammering away...the "guts" fall out the outlet...you might reverse the direction of attack a time or two, but that's how I've always done it...never looked at the cat/cats on my 2.4 though so maybe something is different.
The better way of doing that though is buy an aftermarket low restriction cat...Walker used to make a really good one...
On my Corvette I removed the pre-cats and installed the Walker low restriction converter, then ran the rest of the way through Lawrence Keech Side Pipes...that set up was good for 40+ HP on the dyno
The better way of doing that though is buy an aftermarket low restriction cat...Walker used to make a really good one...
On my Corvette I removed the pre-cats and installed the Walker low restriction converter, then ran the rest of the way through Lawrence Keech Side Pipes...that set up was good for 40+ HP on the dyno
Last edited by CorvetteMongo; 06-11-2016 at 10:54 AM.
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