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Old 10-31-2000, 10:05 PM   #1
tomrichardson
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Member#: 2672
Join Date: Oct 2000
Location: Lakewood, CO USA
Vehicle:
1973 Porsche 914
Porsche Red

Question Removing catalytic converter?

I know it's illegal, but what kind of power increase would somebody expect to see from doing it? I've heard rumors of up to 10 hp. I talked to a specialist in Pocatello, he said Cobb Tuning has a spacer pipe to go in place of the converter. I wasn't able to find it though.

I live in the middle of nowhere in Idaho. So, I'm not too concerned about getting caught because we have no required inspections here.

Just thought I'd ask for some peoples opinions.

Thanks,
Tom Richardson, Jr.
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Old 10-31-2000, 10:20 PM   #2
XT6Wagon
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Post

WHY?? Jeg's sells 2.25" and 2.5" 3 way high flow cats for $52.

If you make the y-pipe equal length, and remove that nasty bend at the end you will get more power. Then put the Cat on after the Y-pipe, and rest easy that you will not get that $10K fine.
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Old 10-31-2000, 11:25 PM   #3
cj917
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MY96 outback wagon

Question

(somewhat related topic) does anyone know what does the small air-inlet tube do, seen on some of the Dynomax cats?
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Old 11-01-2000, 05:23 AM   #4
LUME
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Dirt and Bird Poop

Post

Air Injection? Some cats require a source of clean air to do their "converting"... thus the little air line. If you follow it, it should lead to a little compressor mounted on the engine. In the case of my other Fuji (my isuzu pickup), the air was injected straight into the header, not the cat.
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Old 11-01-2000, 05:44 AM   #5
Basil
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Post

I agree - what's the point of risking the fine, when for the same kind of money, you can get a high flow cat.

Plus, the ever present bugbear of low end loss lurks with the removal of the cats, I believe. A lot of people say that the exhaust size effects back pressure, which is of course true - but they also say in N/A cars, it reduces the low end. From all the tuners I've spoken too, they seem to be pretty much in agreement that the cats provide all the necessary backpressure.

For god's sakes, just get a high flow - I'm not a tree hugger, but there are better ways to get power out of your car.

Basil
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Old 11-01-2000, 07:23 AM   #6
legacyGT00
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Wink

But few cheaper than removing it all together.
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Old 11-01-2000, 08:58 PM   #7
Fitz
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Post

Too cheap to spend the $52 on a high flow cat? You'd rather replace it with a straight pipe that screws over our environment? Some people never cease to amaze me with their ignorance....
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Old 11-01-2000, 09:31 PM   #8
wistful
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c'mon now, don't rip on the poor guy.. jeez.. there were nicer ways of saying that At first, I didn't know hi-flo cats were so cheap, I was gonna go straight pipe. But ever since of learning the cheap ones from Jegs, yes i'm buy a hi-flo cat.

don
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Old 11-03-2000, 12:56 AM   #9
Sunrise City Rider
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Blue Ridge Pearl

Exclamation

I met a guy at an autox that runs a straight pipe and a stromung catback and he claims that he ran a 15.1 at 90?mph! I don't believe that he can duplicate that time though, even with a newer clutch. I also feel it was a problem with the track equipment that gave him that time...
Zee
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Old 11-04-2000, 06:46 AM   #10
george
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Blue Ridge Pearl

Question

Sorry if this is a stupid question...
When replacing my stock cats for Jegs 3-Way HiFlow Cats, would I have to buy 2 or just 1?

If I have to buy just one, what do I do about the gap? And the extra O2 Sensor? (Remember we've got 2 cats and each has an O2 Sensor)

Note: I'm totally new to this, so bare with me.
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Old 11-04-2000, 09:48 AM   #11
wistful
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hehe, i'm totally new to this too.. but I assume that we can run just one. After winter's over, i'm gonna go to a muffler shop that my friend recommended to me and ask. That Y-kink at the end of the headers is really annoying, and I wonder if I can do anything about it....

Don
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Old 11-04-2000, 10:44 AM   #12
XT6Wagon
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Ok here is what you do....

Go to a place that builds race cars, and does exaust work. Yes they exist.

Then you chop the stock Y-pipe into a pair of L's comming off the motor. Then do a nice smoth bends to bring them together so that a 2-1 collector is pointing at the rear bumper.
Then run pipe to where the cat will go. Put cat in with the inlet and outlet along the axis of the car. Have the guy put flanges on the downstream side at least. Then use a Glasspack until close to where the stock exaust goes through the rear bumper. Finish it off with factory routing through the suspention to the rear bumper. Use muffler of your choice.

Note critical things
1. CAT. Must have the cat
2. 2-1 Collector, cheap to buy and better flow than 99.9% of the normal methods to jion two pipes into one
3. glasspack This is here to keep cops off your butt. Minimal restriction also, so straight through ("race") mufflers can be used without the ticket penalties
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Old 11-05-2000, 12:28 AM   #13
wistful
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Post

where do I get a 2-1 collector? and what does it look like? sorry I dunno what these things are...

Don
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Old 11-06-2000, 11:25 AM   #14
kar250c
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Flowmaster makes a great one. Any shop that sells their stuff should be able to get one.
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Old 11-06-2000, 01:58 PM   #15
Yeoman
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Post

Regarding George's question...

Our exhausts are as follows,

o2 sensor-cat1-cat2-o2 sensor.

you'll just make it like this,

o2 sensor-cat1-o2 sensor

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Old 11-07-2000, 12:43 AM   #16
tomrichardson
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Post

XT6Wagon,

Thanks for your comments. How do I contact Jeg's? Do they have a website? I'm interested in getting their 2.5" high flow cat. That seems like a very good price.

Thanks,
Tom Richardson, Jr.
MY00 2.5RS
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Old 11-11-2000, 08:51 AM   #17
2yLiTe
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Question

I don't understand this....I was about to install a Stromung track pipe, and noticed that there's a sensor on the second cat..I thought the MY98s had only one sensor?!?!
If I install this pipe, what am I supposed to do with the extra sensor?

Please help
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Old 11-11-2000, 09:47 PM   #18
XT6Wagon
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Post

Its www.jegs.com
Just use it to get the phone # or order the free catolouge. Otheriwse the site is near useless.

If you talk to them they should have most everything needed for your system
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