I have a friend with a 97 lude and he wants to gut his cat. I think it is worthless and we only make his car run worse. Is this true? What are the benifits and side effects of gutting the cat?? Isnt there a o2 sensor in there? Would doing this make obd2 upset? Thanks

 

Don't, sounds/smells/pollutes like ***. Waste of time, most power will be 1-5 hp, not bad, however can't pass emissions and backfiring which can lead to backpressure and engine wear...

Just something to consider...

 

[QUOTE]Don't, sounds/smells/pollutes like ***. Waste of time, most power will be 1-5 hp, not bad, however can't pass emissions and backfiring which can lead to backpressure and engine wear...QUOTE]

What he said

 

i purchased a test pipe from http://www.testpipes.com it was worth the 40 bucks.
I gained 6 hp on the dyno. Car was loud as hell and it got annoying driving it around. I got it for track use but put it on for the dyno. I would not recommend driving around with it.
And yess it will throw a CEL and Yes it does add performance. and NO do not gut out your cat!!!!!

 

actually, i don't completelly agree....
true it can't pass smog, but if you don't care about smog i say go for it.
but i would make sure you have a nice muffler to cover that noise.
i had mine hollowed with a tanabe super hyper medalion, and it was good. not lout at all, no backfire, and a 6hp gain. if you're considerate about air pollution, then you might want to leave your cat alone.

 

That's a lot like me. I have a new 4-2-1 GReddy header and a Apexi Dunkstyle universal muffler, along w/ some custom 2.5" piping. Do you suggest that when the guy sets it on the ground I gut out my cat? He also said he could make it w/ no cat. What should I do?

 

dont do it , waste of time and money. it doesnt do anything for you but spit of rich exhaust fumes.

 

hahaha, gimme some stuff you're smokin foo..... hahaha
it wil free up some hp guaranteed, unless you have like 3' piping on an N/A set-up, then you won't get anything.
if i had to chose between a stock cat and hollowed cat (performance-wise) i'd take the hollowed cat.
i dyno tested my old prelude after gutting the cat. it resulted in a 6hp peak gain.
lost 1hp in the low rpm, which evened out at 4000rpm, and from there it was nice clean gain.

 

I'm not sure about gutting your cat on the lude. My dad did it to his 89 crx which had a B16A VTEC in there with twin supertrap mufflers. It was loud as hell but the thing flew. I got a powercore race cat for my lude on the way. I hope to see 5hp more.

I'm also looking for any helpful hints with my planned H22a into my Prelude S. If anyone has any hints I posted the subject. Thanks.

 

Tell us how it goes.

 

i've run a testpipe on my old h22a accord and gutted the cat before that. dont'gut the cat, it's a waste. too much turbulence anyway within the cat for it to be much any good. however, on obd2 cars like my old accord you will trigger the secondary with a test-pipe, be prepared for that.

i'm currently running another test pipe from test-pipe.com on my 93 vtec.

you can definitely feel the extra power top end. can't really feel much down low. but at around 6500-up it's noticeable.

sure, it's gonna smell but it's a cheap mod. sorry, there is only backfiring depending on the type of muffler you have.

if you have a straight through muffler then think twice as things get really loud. but i personally have run apexi ws on both the accord and prelude and it's very quiet. hardly hear it.

for $40 the gains are there!

 

dang im gonna be making my 2.5in testpipe to mate to my modded DC header. The test pipe goes to a N1 catback that suckers gonna be loud

 

just get a testpipe and O2 simulator if u have a obd2 car...u won't throw a cel with the O2 sim. because as the name implies, it simulates the second O2...keep the stock cat intact if u have emissions to pass....testpipe adds performance because there is nothing obstructing the exhaust passage....with a cat, u have the honeycomb catalyist obstructing the flow of the exhaust

 

Uh, are you lost? - no offence, you just agreed w/ me. I never disagreed or said anything considering a test pipe...

Think before you contradict yourself....

 

uh, no.....are you lost???
i just didn't agree with you:
you said "don't", i said if the person doesn't care about smog he should go for it.
you said "it's a waste of time" i think a free 6hp gain is not a waste of time.
and i don't think i "contradicted" myself. read carefully next time and then write your replies. i have nothing against you, but in this case you're wrong.

 

Okay, I see your point. You just didn't explain why you disagreed with me (somewhat). But anyway, 6 hp gain is extremly rare! He has all the info he needs, hopefully we helped him out!


[Modified by w00t!, 6:34 PM 5/13/2002]

 

alright i see that everyone choose the $40 test pipe over gutting.....but if u were to see the difference of a free flow cat and a gutted cat there is not much difference...i did both and i think either way would work but hey if u got nothing to lose a free 6hp gain is not bad.

 

dont bother gutting it, definately go with a high flow.

http://www.team-integra.net/se...ID=24

If you shop around and do some research for a good cat, you will find that a well designed one will flow almost just as well as a test pipe, however you wont get any CELs, you wont be polluting, and you will pass emissions.

If you read the link i just posted, a carsound 2.25" cat flowed 342.7 cfm, meanwhile the testpipe flowed 407.1 cfm, the ~60 cfm difference never showed a difference on the dyno that was also posted in that article....

Dont bother gutting, you're better off trying to sell the OEM cat off (if you have lower mileage), and using that money to get a highflow cat...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 976 &raquo;</TD></TR><TR><TD CLASS="quote">Don't, sounds/smells/pollutes like ***. ..</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mattmw88 &raquo;</TD></TR><TR><TD CLASS="quote">That's a lot like me. I have a new 4-2-1 GReddy header and a Apexi Dunkstyle universal muffler, along w/ some custom 2.5" piping. Do you suggest that when the guy sets it on the ground I gut out my cat? He also said he could make it w/ no cat. What should I do? </TD></TR></TABLE>

Get a high flo cat.