Gutted Cats vs. test pipes

[BATMANs]

Is gutting the cats difficult?

How do they sound compared to test pipes?

THe reason I'm considering gutted cats is that the cats are easy to view from below the bumper just in case I pulled over for visual inspection.

 

[AdvansCPAP]

Gutting the cats is easy if you use a drill with a foot long bit. The bigger the bit, the faster. Don't waste your time trying to punch them out using anything else. I don't know if there's a difference in sound between gutted cats and test pipes..but most likely not that much since a hole is a hole. You're better off with gutting for the sake of johnny law. Just make sure you have a spare set if you need to ever smog the SOB.

 

[BATMANs]

so once u drill them through will the cat start to crumble apart?

Idon't won't any loose pieces rattling around in any part of my exhaust system.

 

[KooLaid]

What about getting a set of old cats from another car, almost any car and punching a hole through it. Then slide a pipe through it to make a set of test pipes? Most places wouldn't even know what oem cats on the nsx looks like or woudl they even be able to tell the difference in cats from the years the nsx was made.

 

[BATMANs]

I have thought of that, but the economics to fabricate one (ie- cutting, welding, flanges, etc.) may not make any sense as oppose to procuring used OEM ones for cheap.

Anyone use a 10 gauge shotgun to expedite the gutting process?

 

[AdvansCPAP]

so once u drill them through will the cat start to crumble apart?

Idon't won't any loose pieces rattling around in any part of my exhaust system.

Yes, and then you can pull everything completely out. Doing each cat takes about 15 minutes. It's as stealth as you can get. If you're ever worried about the exhaust getting louder after doing it, just get some new tips with resonators and you're good to go.

 

[BATMANs]

I'm not too worried about sound since I want to drive WOT by Koolaid's 'hood so that his neighbors think that he is the catalyst in making their home values drop in addition to the sub prime fiasco.

 

[goldNSX]

Why messing up the cats you can sale as long as they work properly if you can buy cheap test pipes?

 

[BATMANs]

read above more carefully.

 

[goldNSX]

read above more carefully.

I don't know why? Gutting the cats is removing the inside of the cats housing and mount them again. You may gain power but the car begins to stink. :wink: Soundwise I'd expect them to be louder but not as pitched the testpipes.
We don't have a visual inspection here if the cats are mounted we have a MOBILE SMOG TEST. If you fail that with or without the cats they'll kick your a**!

 

[RON98]

you can use a steel rod and plunge the internals to death :biggrin:

its a good idea to gut your cats if youdont need them for smog since if a police pulls you over and instead of admiring your nsx, checks to see if you have cats.... you wont pass with the test pipes.

but what police man knows what to look for on an nsx anyways.

test pipe away.

happy motoring.

 

[Angelo08]

You cant see them anyways as i suppose your car is dropped. Anyways when i originally gutted my cats way back, before my test pipes came i had particles in there that i could get out completely which caused a stupid annoying noise. Eventually overtime they cleared on their own, but by that time my test pipes arrived. Get the Random Hi-flow cats which are SMOG lega and maintain within the same sound as the test pipes. No real power gains.

 

[lithiumus]

Not sure if they have been discontinued, but in Japan some JDM aftermarket company made a great set of NSX test pipes that had the mounting points for the OEM heat shields. Fantastic idea really, the OEM heat shields are fairly light and completely cover up the actual cats...

 

[BD]

I had custom test pipes made for $150 buck from a local muffler shop.

 

[BATMANs]

You cant see them anyways as i suppose your car is dropped. Anyways when i originally gutted my cats way back, before my test pipes came i had particles in there that i could get out completely which caused a stupid annoying noise. Eventually overtime they cleared on their own, but by that time my test pipes arrived. Get the Random Hi-flow cats which are SMOG lega and maintain within the same sound as the test pipes. No real power gains.

All the CHP needs to do is to get on all 4 limbs and he can see them.

 

[Brooklynzson]

I have gutted pipes and i love the way they sound and its kinda better than test pipes because you might get that one cop that will look under your car and see test pipes and want to be a **** about it...To gut mines i used a pipe thats about 2 ft. long with a hammer and just went to work took about half hour total

 

[popsicle]

i'm gutting my cats this weekend. any advise?

 

[Lonestranger]

Too late for any advice, sounds like you're minds made up!!:biggrin:

QUOTE=popsicle;890482]i'm gutting my cats this weekend. any advise?[/QUOTE]

 

[popsicle]

haha yeah i meant in terms of best way to proceed with it. and pitfalls to avoid

 

[Lonestranger]

Yeah - don't breath in while you're attacking the cats (unless you have a respirator) Those "precious" metals can kill ya!!::wink:

haha yeah i meant in terms of best way to proceed with it. and pitfalls to avoid

 

[sahtt]

I'm assuming you don't have emissions testing.

Just be weary that if for some reason you 'must' have cats right away, OEM units are excruciatingly expensive [at least where I checked].

For instance, your sticker expires, you get pulled over, and you need to get a test done else pay a steep fine. Can you find used units before then? You have to sell your car due to an emergency but unless you get cats you limit all potential buyers to Indiana and wherever else don't do emission testing.

I'd just get test pipes, the difference between those and gutted cats decible wise isn't significant IMO. Not to mention the gutted cats often don't smell very good if they are old units. Used cats are cheap but not too plentiful.

 

[davidf]

Even if you gut them, I'd look around for a used set just to keep on hand.

 

[BATMANs]

i'm gutting my cats this weekend. any advise?

 

[nsxtasy]

On a normally aspirated car, they're not going to add any performance. They're just going to make your car stink, and add to pollution in the environment. Leave them alone.

 

[AR]

I have thought of that, but the economics to fabricate one (ie- cutting, welding, flanges, etc.) may not make any sense as oppose to procuring used OEM ones for cheap.

Anyone use a 10 gauge shotgun to expedite the gutting process?

You can't be serious!