Clogged CAT?

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umcamara
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Re: Clogged CAT?

Post by umcamara »

Mnemonic wrote:run the car for a little while, jack it up, grab the long handle breaker bar, it'll pop loose :) let it cool then go with a regular ratchet
That's a smart idea, just run the run car for awhile instead of using the torch to heat up the bolts. Only downside is, now everything's hot, and you gotta be a little bit more careful.
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fowljesse
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Re: Clogged CAT?

Post by fowljesse »

A hollowed cat flows better than a new one.
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fighttillyoudie0
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Re: Clogged CAT?

Post by fighttillyoudie0 »

fowljesse wrote:A hollowed cat flows better than a new one.

When the CAT is Hollowed out does the Diameter of it affect the backpressure in anyway?
Or is the cat the same size as the pipe it's connected to?(Like meaning when hollowed it would be like a straight test pipe?)
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Ryan
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Re: Clogged CAT?

Post by Ryan »

aerodynamics is a very complex science... the movement of air has to do with diameters, the way the diameters change, the frequency of the pressure changes, the amplitude of the pressure changes, temperature, temperature changes, the curves.... lots and lots and lots. But sometimes a bigger path isn't neccesarily the easier path.
Personally, for all the difference a cat may or may not make, I would keep it, to help with things like passing emissions, and maybe saving the environment, if you believe in that.

But clogged, yes, I would think that would sap performance. Clogged exhaust should act similar to clogged intake, I would think, which I know can kill vehicles....
Last edited by Ryan on May 28th, 2008, 10:44 pm, edited 1 time in total.
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fighttillyoudie0
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Re: Clogged CAT?

Post by fighttillyoudie0 »

Ryan wrote:aerodynamics is a very complex science... the movement of air has to do with diameters, the way the diameters change, the frequency of the pressure changes, the amplitude of the pressure changes, temperature, temperature changes, the curves.... lots and lots and lots. But sometimes a bigger path isn't neccesarily the easier path.
Personally, for all the difference a cat may or may not make, I would keep it, to help with things like passing emissions, and maybe saving the environment, if you believe in that.
I would like to keep it the way it is, but I do believe it is clogged... Which is really eating at the performance of my car. I had a bad oxygen sensor and my car was running pretty rich for quite sometime. I'm sure enough time to fowl it... So yeah...
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fighttillyoudie0
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Re: Clogged CAT?

Post by fighttillyoudie0 »

Okay... So I can't get one of the nuts completly off. It will come off half way the it gets like stuck and won't come off any further. Is the threads stripped? or maybe dirty? Has anyone else had this problem before?
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Re: Clogged CAT?

Post by fowljesse »

Yes. You'll probably have to cut it.
'93 GS - P&P DE w/ ZE exh. cams/ pistns, KLG4 IM, 65mm TB, MSnS, Phenos, K&N RAI, UDP, Grnd wires, rear batt, filld MM, torq strt, TWM short shftr, Exedy, Lng tube hdrs 2.5" Side exhaust, H&R sprngs, Poly bushngs, strutbars, Alum. crss mmber&tiebar, 22mm swybar, solid links, Direzzas, leather int, Alpine 9805 stereo & alrm, keyless entry, 10 Boston Accoustics spkrs, Prjectrs, Blaster2, CF hood, FG hatch, Lexan
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fighttillyoudie0
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Re: Clogged CAT?

Post by fighttillyoudie0 »

So I heard that if you put your hand over your Exhaust pipe that the backpressure should be enough to push your hand right off the pipe? Is that true? Cuz' if it is then my CAT must be clogged because I can put my hand over my exhaust pipe with hardly any pressure pushing on my hand. :shrug:
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