Cat Removal-How & What?

Will

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This is a great topic to discuss. I am considering doing some upgrades pretty soon and am wondering whether to just remove the cats altogether or replace them with high flow cats when I do the header/exhaust upgrade. Aside from destroying the environment and the check engine light (which Apex has a cure for), are there any other concerns? I have heard that sometimes you can experience unexpected bursts of power.

Thanks,

-Will
 
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Yellowing sills covered many times do a search.

Comment on Cat's

Removing cats can cause flames out the exhaust. Looks cool at night but if you are running rich the real bumper cover can burn. It has happened!

Good news is that without cats you gain a few hp depending on the motor.

My ACR exhaust was fabricated so the cats(high flow) can be removed and a straight pipe inserted for the extra hp if I want to play. Dan Cragin can help if this is what you want.

High flow cats are a good compromise between gaining hp and being kind to the earth.
 

SapphireGTS

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Cool. Im in the works of wanting to do this. Would I get flames with high flow cats? Or only if I had straight pipe?

This is my next step so Ill take some pics.
smile.gif
 

RECOIL

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Without mentioning names, I've been told that the difference between no cats and a "free flowing high flow cat" is ~2HP.

I'll sacrifice the 2HP for a car that doesn't smell like a gas station.

Steve
 
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No Cats=Flames
Hi Flow Cats=HP+Clean Air

All high flow cats are not equal in hp gain. Call Dan Cragin he evaluated several for use on my car. On my car No Cats=30HP vs stock Cats. (Motor by Caldwell, removed and re-installed by Dan).
HP delta on back to back runs on CDI's engine Dyno.
 

LTHL VPR

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We have experimented with the effects of stock cats, 'high-flow' cats, and no cats on my 98 GTS and my 2001 ACR. He are the pros and cons we noticed:

PROS (no cats):
More hp/tq (9-14 rwhp and 7-10 rwtq over stock cats)
Side sills are cool by comparison
Flames (can be pro and/or con)
Sounds increases noticeably (can be pro and/or con)

CONS (no cats):
Not emissions friendly
Against the law
Check engine light on late 98-2001+ Vipers (OUR SNAKE BOX CURES THIS!)
Surging under light throttle/cruising conditions(OUR SNAKE BOX CURES THIS!)
Lots more popping on deceleration
Rear bumper get more black soot, but no damage from flames
Flames (can be pro and/or con)
Sounds increases noticeably (can be pro and/or con)
____________________
PROS (high flow cats)
More hp/tq (app. 5 rwhp and 4 rwtq over stock cats)
Side sills are cooler than stock cats, but still get hot
Rear bumper get more soot
No Flames (can be pro and/or con)
Sounds increases (can be pro and/or con)
Emissions friendly- should pass the sniffer

CONS (high flow cats)
Still against the law (must be certified for a Viper)
More popping than stock on deceleration (less than cat-less)
Sounds louder and tends to be slightly more raspy than stock

HOPE THIS HELPS!
We keep high-flow cats and Snake Boxes in stock!!
Thank you.
-Wayne (LTHL VPR)
 

bad viper

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This is what I did. The cats were removed..Borla Sportsman stainless "mufflers" went in their place. These are 14" long 3" inlet ,3" outlet, 3 1/2 in diameter..Used primarily on midget
racers. Loud, distinctive,ETC ETC
 

LTHL VPR

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Thanks SOCRATES and Gary. Since this post, I have received several inquiries about our Snake Boxes. I announced this new product to the Viper Board about a month ago. So far we have sent many sets out to customers, and no complaints.
Here is a link for the details: http://vca1.viperclub.org/ubb/Forum24/HTML/000121.html
The 'special price' is still effective. We should be getting our second batch in a week or two.
JUSTYN- Any knowledgeable exhaust/muffler shop should be able to remove the stock cats and replace them with either high-flow cats or straight pipes. The only hitch you might run into is whether or not they are willing replace it with a straight pipe since it is illegal to run without cats. As for the Snake Boxes, installation is a snap and only takes about 15-20 minutes max once you are under the car.
Take Care.
-Wayne
 

Nadine UK GTS

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Catless gives flames, (fun if a poxy motor rides close on your butt through town). I can get the flames to show in my side mirrors sometimes, rear fascia just gets a little tinged. Some of us were just born to be naughty! (apologies to the tree-huggers)


You must be registered for see images
 

ntmatter

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So, does anyone make a metal exhaust tip shield that can be easily mounted on the back bumper? I have the snake-oyl pipes, which are close enough to the plastic to make we worry about warping. A metal plate of some sort (like Hennessy put on the 800) would hopefully protect against this and soot from cat-lack.
 

Robert1994

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How does the cat removal work on 1st gen cars ?
I already have a lot of rumbling when decelerating,
I love it. With out cat's will I also get flames ?
WOW ! Love it !
 
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