hollow out catalytic converter - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Gordo714 · 03-20-2009, 06:01 PM

have my exhaust off right now and was thinking about hollowing out the CAT but dont know what it would be like. i already tried a test pipe did not like it becasue it leaked now i want to try this any input will help

will it sound deeper or more raspy like a Honda???

ps. stock exhaust. not after market at all

straight OEM lol

thanks

Tenchuu · 03-20-2009, 06:06 PM

what engine? but generally no, stock S14s have a hollowed out car factory, but a big ass one in the DP

Gordo714 · 03-20-2009, 06:09 PM

its on a KA n/a i am sitting here in my garage debating on doing it or not

Jonnyblaze · 03-20-2009, 06:09 PM

Don't get caught. That's highly illegal.

midnightouge · 03-20-2009, 06:10 PM

Sell it and buy a test pipe.

Gordo714 · 03-20-2009, 06:13 PM

yeah i know its illegal but not as illegal as driving with out anexhaust for the past 2 days pretty sickky but way to much attention

na test pipe is ruled out already had one.

lflkajfj12123 · 03-20-2009, 06:18 PM

i drove without an exhaust for almost a year

never got bothered for it

Jonnyblaze · 03-20-2009, 06:24 PM

A test pipe is better. Just install in correctly next time.

Gordo714 · 03-20-2009, 06:31 PM

where do you live though?

Gordo714 · 03-20-2009, 06:33 PM

im over it so cal sun is to nice going to the beach laaaaate check thread tomorrow and thanks to everyone

The Chad · 03-20-2009, 06:56 PM

hollow it out if it is not already from factory. I noticed very little difference in sound when i installed my Hotshot 4-1 headers/cat delete. That stock muffler eats up all kinds of engine noise!

03-20-2009, 07:58 PM

dont do it on an NA car... even on a turbo car, i wouldnt do it.

Anto · 03-20-2009, 08:24 PM

wtf.. dont do it on a stock exhaust

GSXRJJordan · 03-20-2009, 08:30 PM

Keep the cat intact, use a resonated test pipe with the correct gaskets - it won't leak, will sound better (deeper), and throw that cat back in for smog.

Stratokat · 03-20-2009, 08:46 PM

Quote:

Originally Posted by GSXRJJordan

Keep the cat intact, use a resonated test pipe with the correct gaskets - it won't leak, will sound better (deeper), and throw that cat back in for smog.

what he said

z2roll4life7 · 03-20-2009, 09:00 PM

Hollowed out Cats have been proven to make LESS hp get a Test pipe and bolt it up right will make more power N/a or Turbo

The Chad · 03-20-2009, 09:31 PM

well here in VA we don't have to pass any kind of smog...sooo when the cat goes bad, it's a big money saver to just gut the catalyst

And I noticed little to no difference in power plus or minus.

03-20-2009, 09:41 PM

what is the fucking point of running w/o a cat?

it doesnt make a fuck worth of sense.

some things like EGR or charcoal canister, i give a fuck about. but things like the cat is NECESSARY on like, 99% of the cars out there (minus race-cars, imo). so seriously, what are you gaining for the amount you are polluting? run a cat and quit being a pussy.

genericforumname · 03-20-2009, 09:57 PM

I agree I have a video of the 800+hp top secret skyline only making a difference of 8hp on a dyno when switching from a test pipe to a high flow cat, if you do anything just buy one of those, plus your car stays legal. Besides if your on stock exhaust anyway power obviously isn't super high on your car anyway so why bother?

03-20-2009, 10:39 PM

omoogmogmogmomgomogmogmomgmgomgoogmomgomomgoomg!!! !

i neeeeeeeeeeeeeeed that EXTRA 8hp to win my street races, y0!!!!!!

seriously.

Sileighty_85 · 03-20-2009, 10:42 PM

Gutting a cat on an N/A does you no good at all it actually hurts you
I have seen many Articles of ppl dynoing a stock cat, gutted cat and a test tipe

from what I've read On N/A cars
Gutted cat will you cause you too lose power due to the turbulence created in the cat causing back pressure
a test pipe gives you about +1 hp

I cant imagen it being that much more on a turbo'd car

So its really not worth fucking with

Im with Mike leave it alone

racepar1 · 03-20-2009, 10:47 PM

Hollowing out your cat is not a good idea. First off your car will sound like shit, and second it restricts flow (possibly more then a cat does) due to what a big empty chamber does to the airflow through it.

HYPNOTIK · 03-20-2009, 11:08 PM

Quote:

Originally Posted by Sileighty_85

Gutting a cat on an N/A does you no good at all it actually hurts you
I have seen many Articles of ppl dynoing a stock cat, gutted cat and a test tipe

from what I've read On N/A cars
Gutted cat will you cause you too lose power due to the turbulence created in the cat causing back pressure
a test pipe gives you about +1 hp

I cant imagen it being that much more on a turbo'd car

So its really not worth fucking with

Im with Mike leave it alone

^I agree^

sliksta1 · 03-20-2009, 11:22 PM

just leave it alone. nuff said.

DDDsquad_s13panda · 03-20-2009, 11:36 PM

im runnin gutted cat to 2.50in. piping to greddy.

my car dont sound like a honda with an APEXi but its almost up there..

dont like it what so ever. but i have n choice. my cat was all busted up inside holding up way too much backpressure causing the bolts to loosen and fall on the freeway, next thing you know, i was on open header draggin my exhaust.

but id get a cat. OEM if you can get one. the aftermarket once the muffler shop sells are booty. besides the magnaflow high flow cat.

but yeah oh btw, i have N/A SR20DE.

drifter_for_life06 · 03-20-2009, 11:49 PM

catco high flow FTW

murda-c · 03-20-2009, 11:56 PM

no cats will make your car smell funny.

timmigans · 03-20-2009, 11:57 PM

i hollowed out my cat. welded a pipe on the inside so it looks legal. runs fine and sounds fine. but thats in new york. we dont have smog tests like you do in cali.

HYPNOTIK · 03-21-2009, 12:34 AM

Quote:

Originally Posted by timmigans

i hollowed out my cat. welded a pipe on the inside so it looks legal. runs fine and sounds fine. but thats in new york. we dont have smog tests like you do in cali.

This is also a good option, just as good as a test pipe.

The Chad · 03-21-2009, 05:46 AM

Join me!!! East Coast unite and trash the environment! (kidding) haha I know not having a catalyst on a car is bad for the environment. I know of the limited gains or even negative numbers one may see on a Dyno. But when my cat started smelling like rotten eggs on my S14, i finally put on my Hotshot 4-1 (deletes cat) and no more smelly exhaust and much cheaper (free) than the $$$$ stock cat. I'll stop saying it's ok to do i guess

I was outnumbered. I really just didn't notice any difference in sound or pick-up soooo I just figured that it was a great alternative to replacing more $$$ parts?

03-20-2009, 06:01 PM	#1
Gordo714 Zilvia Junkie Join Date: Jun 2008 Location: 714 Posts: 510 Trader Rating: (10) Feedback Score: 10 reviews	hollow out catalytic converter have my exhaust off right now and was thinking about hollowing out the CAT but dont know what it would be like. i already tried a test pipe did not like it becasue it leaked now i want to try this any input will help will it sound deeper or more raspy like a Honda??? ps. stock exhaust. not after market at all straight OEM lol thanks

03-20-2009, 06:09 PM	#4
Jonnyblaze Zilvia Member Join Date: Feb 2007 Location: Oxnard, CA Posts: 285 Trader Rating: (1) Feedback Score: 1 reviews	Don't get caught. That's highly illegal. __________________ '91 Hatch - Work in Progress

03-20-2009, 06:10 PM	#5
midnightouge Zilvia Addict Join Date: Jun 2007 Location: BayArea Posts: 749 Trader Rating: (12) Rides Gallery: midnightouge Feedback Score: 12 reviews	Sell it and buy a test pipe. __________________

03-20-2009, 06:24 PM	#8
Jonnyblaze Zilvia Member Join Date: Feb 2007 Location: Oxnard, CA Posts: 285 Trader Rating: (1) Feedback Score: 1 reviews	A test pipe is better. Just install in correctly next time. __________________ '91 Hatch - Work in Progress

03-20-2009, 08:24 PM	#13
Anto Zilvia Addict Join Date: Jan 2006 Location: California Posts: 862 Trader Rating: (2) Feedback Score: 2 reviews	wtf.. dont do it on a stock exhaust __________________

03-20-2009, 06:06 PM	#2
Tenchuu Post Whore! Join Date: Apr 2004 Location: Oregon Age: 42 Posts: 2,474 Trader Rating: (8) Rides Gallery: Tenchuu Feedback Score: 8 reviews	what engine? but generally no, stock S14s have a hollowed out car factory, but a big ass one in the DP

03-20-2009, 06:13 PM	#6
Gordo714 Zilvia Junkie Join Date: Jun 2008 Location: 714 Posts: 510 Trader Rating: (10) Feedback Score: 10 reviews	yeah i know its illegal but not as illegal as driving with out anexhaust for the past 2 days pretty sickky but way to much attention na test pipe is ruled out already had one.

03-20-2009, 06:18 PM	#7
lflkajfj12123 Join Date: Apr 2007 Location: 　　　　　　　　 Posts: 8,483 Trader Rating: (20) Feedback Score: 20 reviews	i drove without an exhaust for almost a year never got bothered for it

03-20-2009, 06:31 PM	#9
Gordo714 Zilvia Junkie Join Date: Jun 2008 Location: 714 Posts: 510 Trader Rating: (10) Feedback Score: 10 reviews	where do you live though?

03-20-2009, 06:33 PM	#10
Gordo714 Zilvia Junkie Join Date: Jun 2008 Location: 714 Posts: 510 Trader Rating: (10) Feedback Score: 10 reviews	im over it so cal sun is to nice going to the beach laaaaate check thread tomorrow and thanks to everyone

03-20-2009, 06:56 PM	#11
The Chad Zilvia Addict Join Date: Feb 2007 Location: Richmond, VA Age: 44 Posts: 943 Trader Rating: (0) Feedback Score: 0 reviews	hollow it out if it is not already from factory. I noticed very little difference in sound when i installed my Hotshot 4-1 headers/cat delete. That stock muffler eats up all kinds of engine noise!

03-20-2009, 07:58 PM	#12
ixfxi Guest Posts: n/a	dont do it on an NA car... even on a turbo car, i wouldnt do it.

03-20-2009, 08:30 PM	#14
GSXRJJordan Post Whore! Join Date: May 2006 Location: San Diego, CA Posts: 9,135 Trader Rating: (19) Rides Gallery: GSXRJJordan Feedback Score: 19 reviews	Keep the cat intact, use a resonated test pipe with the correct gaskets - it won't leak, will sound better (deeper), and throw that cat back in for smog. __________________ Jordan Innovations has a new web site! www.JordanInnovations.com -- All your favorite FD Pro Drifters love it, trust me -- www.JordanInnovations.com

03-20-2009, 09:00 PM	#16
z2roll4life7 Zilvia Member Join Date: Mar 2009 Location: charlotte Age: 37 Posts: 213 Trader Rating: (3) Feedback Score: 3 reviews	Hollowed out Cats have been proven to make LESS hp get a Test pipe and bolt it up right will make more power N/a or Turbo

03-20-2009, 09:31 PM	#17
The Chad Zilvia Addict Join Date: Feb 2007 Location: Richmond, VA Age: 44 Posts: 943 Trader Rating: (0) Feedback Score: 0 reviews	well here in VA we don't have to pass any kind of smog...sooo when the cat goes bad, it's a big money saver to just gut the catalyst And I noticed little to no difference in power plus or minus.

03-20-2009, 09:41 PM	#18
ixfxi Guest Posts: n/a	what is the fucking point of running w/o a cat? it doesnt make a fuck worth of sense. some things like EGR or charcoal canister, i give a fuck about. but things like the cat is NECESSARY on like, 99% of the cars out there (minus race-cars, imo). so seriously, what are you gaining for the amount you are polluting? run a cat and quit being a pussy.

03-20-2009, 09:57 PM	#19
genericforumname Zilvia Member Join Date: Sep 2007 Location: Florida, where we prove that shit does in fact run down hill Age: 36 Posts: 229 Trader Rating: (0) Feedback Score: 0 reviews	I agree I have a video of the 800+hp top secret skyline only making a difference of 8hp on a dyno when switching from a test pipe to a high flow cat, if you do anything just buy one of those, plus your car stays legal. Besides if your on stock exhaust anyway power obviously isn't super high on your car anyway so why bother?

03-20-2009, 10:39 PM	#20
ixfxi Guest Posts: n/a	omoogmogmogmomgomogmogmomgmgomgoogmomgomomgoomg!!! ! i neeeeeeeeeeeeeeed that EXTRA 8hp to win my street races, y0!!!!!! seriously.

03-20-2009, 10:42 PM	#21
Sileighty_85 Post Whore! Join Date: Dec 2006 Location: Misawa, Japan Posts: 6,815 Trader Rating: (8) Feedback Score: 8 reviews	Gutting a cat on an N/A does you no good at all it actually hurts you I have seen many Articles of ppl dynoing a stock cat, gutted cat and a test tipe from what I've read On N/A cars Gutted cat will you cause you too lose power due to the turbulence created in the cat causing back pressure a test pipe gives you about +1 hp I cant imagen it being that much more on a turbo'd car So its really not worth fucking with Im with Mike leave it alone __________________ 後輪駆動車１番 1989 Built SR GT2871R -363whp 1998 S14 W/RB25- 250ish (For Now) 1986 SR86 - 200ish 1990 R32 GTR - 320hp Don't Buy Engines from JDM-Online http://zilvia.net/f/businesses/207457-jdm-online.html Don't Buy XS-Power or SSAC Shit

03-20-2009, 10:47 PM	#22
racepar1 Post Whore! Join Date: Jul 2007 Location: Simi Valley, CA Age: 42 Posts: 9,006 Trader Rating: (106) Rides Gallery: racepar1 Feedback Score: 106 reviews	Hollowing out your cat is not a good idea. First off your car will sound like shit, and second it restricts flow (possibly more then a cat does) due to what a big empty chamber does to the airflow through it.

03-20-2009, 11:22 PM	#24
sliksta1 Zilvia Member Join Date: Jun 2007 Location: NM Age: 41 Posts: 229 Trader Rating: (6) Feedback Score: 6 reviews	just leave it alone. nuff said. __________________

03-20-2009, 11:36 PM	#25
DDDsquad_s13panda BANNED Join Date: Dec 2007 Location: Fontana, IE. Age: 38 Posts: 550 Trader Rating: (7) Feedback Score: 7 reviews	im runnin gutted cat to 2.50in. piping to greddy. my car dont sound like a honda with an APEXi but its almost up there.. dont like it what so ever. but i have n choice. my cat was all busted up inside holding up way too much backpressure causing the bolts to loosen and fall on the freeway, next thing you know, i was on open header draggin my exhaust. but id get a cat. OEM if you can get one. the aftermarket once the muffler shop sells are booty. besides the magnaflow high flow cat. but yeah oh btw, i have N/A SR20DE.

03-20-2009, 11:49 PM	#26
drifter_for_life06 Zilvia Addict Join Date: Sep 2005 Location: New Freedom, PA Age: 36 Posts: 775 Trader Rating: (6) Feedback Score: 6 reviews	catco high flow FTW __________________ RPS13: +.020" 2871r 264's AEM EMS http://enjukuracing.com/#_l_4s

03-20-2009, 11:56 PM	#27
murda-c Post Whore! Join Date: Jan 2007 Location: Montgomery County, MD Age: 37 Posts: 3,198 Trader Rating: (1) Feedback Score: 1 reviews	no cats will make your car smell funny. __________________

03-20-2009, 11:57 PM	#28
timmigans Join Date: Jul 2008 Location: long island, ny Posts: 29 Trader Rating: (0) Feedback Score: 0 reviews	i hollowed out my cat. welded a pipe on the inside so it looks legal. runs fine and sounds fine. but thats in new york. we dont have smog tests like you do in cali.

03-21-2009, 05:46 AM	#30
The Chad Zilvia Addict Join Date: Feb 2007 Location: Richmond, VA Age: 44 Posts: 943 Trader Rating: (0) Feedback Score: 0 reviews	Join me!!! East Coast unite and trash the environment! (kidding) haha I know not having a catalyst on a car is bad for the environment. I know of the limited gains or even negative numbers one may see on a Dyno. But when my cat started smelling like rotten eggs on my S14, i finally put on my Hotshot 4-1 (deletes cat) and no more smelly exhaust and much cheaper (free) than the $$$$ stock cat. I'll stop saying it's ok to do i guess I was outnumbered. I really just didn't notice any difference in sound or pick-up soooo I just figured that it was a great alternative to replacing more $$$ parts?