Removing the cat.?
#1
Registered!!
Thread Starter
Join Date: Aug 2004
Posts: 55
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 Removing the cat.?
Right now I have a cat back exhaust, now thursday i'm gonna buy me headers, so i was thinking of getting a pipe to replace the catalyc converter, but this guy was telling me that if i remove the cat. there will be no back preassure and eventually would cause long term damage to the engine, is this true or would the engine be fine if i remove the cat?
#3
Registered!!
Thread Starter
Join Date: Aug 2004
Posts: 55
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 I'll just put the old cat back on when the emmisions test comes, i dont think the check engine light will be on because there is a plug for the oxygen censor, how bad does your car smell?
#5
OMNES AD UNUM
iTrader: (3)
Join Date: Sep 2003
Location: NOR-CAL
Posts: 5,855
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 309 the car smell = exhaust fumes. running the car with no cat = hi flowing... thus creating more pollution while giving the car "better performance". thats why it smells, but its not that bad of a smell.
check engine light/malfunction indicator lamp WILL be on if you run a straight pipe and catless. i bought the megan hi flow cat test pipe which is the downpipe after the header and replaces the cat. i plugged in my o2 sensor into that, malfunction lamp still on. only way to get rid of that indicator lamp is by o2 simulator.
ask that guy "how would it effect the engine in long terms?"
check engine light/malfunction indicator lamp WILL be on if you run a straight pipe and catless. i bought the megan hi flow cat test pipe which is the downpipe after the header and replaces the cat. i plugged in my o2 sensor into that, malfunction lamp still on. only way to get rid of that indicator lamp is by o2 simulator.
ask that guy "how would it effect the engine in long terms?"
#7
iTrader: (14)
Join Date: Jul 2004
Location: Las Vegas, NV
Posts: 3,120
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 272 i was wondering.... if the o2 simulator is in thhere which turns off the CEL... then does that mean it would be able to pass emission check... cause all they do is plug into the ODB2 connector which reads the 02 sensor... but if u have the simulator then it should be fine.. wouldnt it??
#8
I just burnt my tongue
iTrader: (8)
Join Date: Mar 2004
Location: Chino Hills, CA
Age: 37
Posts: 4,990
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 295 my homie removed his cat out of his civic and when he drives its loud as hell and it spews out black smoke...u'll get caught easy...he got caught on the 2nd day without it on cuz cops saw taht and gave him a fixer
#11
iTrader: (14)
Join Date: Jul 2004
Location: Las Vegas, NV
Posts: 3,120
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 272 well... for me i still got the resonator in there so it still sound like a really soft aftermarket exhaust.. not loud at all.. no mod thats costs $100 or more that only gives u 1 or 2hp is worth it... u would be spending a sheit load of cash just to gain 10hp even at that... but to me that just means that much more closer to a higher hp... but i got my cat removed for free... even if it only does give 1/2hp or 1 hp it still wasnt anything outta pocket for me.. IMO
#15
OMNES AD UNUM
iTrader: (3)
Join Date: Sep 2003
Location: NOR-CAL
Posts: 5,855
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 309 i dont see how giving your exhaust better flow will decrease torque/horsepower works =\ and im pretty sure backpressue doesnt play that much of an important role either..
i have the megan hi flow test pipe which replaces the cat converter along with a downpipe. its 2.5" thick i believe and serves a purpose: hi flow, better performance giving quicker throttle response, cant really claim hp or torque gains, but im assuming 1hp+.
as for pollution, sounds... im running mine with oem exhaust so its still quiet and does not spew out any black smoke at all. matter of fact, no smoke is visable during the daytime unless i just started up my car to warm it up, after few minutes, no sign of smoke. BUT you can smell the exhaust fumes. by having my stock exhaust on, im pretty sure it would fool the cop if he were to smell any fumes.
i have the megan hi flow test pipe which replaces the cat converter along with a downpipe. its 2.5" thick i believe and serves a purpose: hi flow, better performance giving quicker throttle response, cant really claim hp or torque gains, but im assuming 1hp+.
as for pollution, sounds... im running mine with oem exhaust so its still quiet and does not spew out any black smoke at all. matter of fact, no smoke is visable during the daytime unless i just started up my car to warm it up, after few minutes, no sign of smoke. BUT you can smell the exhaust fumes. by having my stock exhaust on, im pretty sure it would fool the cop if he were to smell any fumes.
#16
7thgen Power Maker
iTrader: (74)
Join Date: Sep 2003
Location: Buffalo, NY, US
Posts: 9,048
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 0
Originally Posted by sokka7
Right now I have a cat back exhaust, now thursday i'm gonna buy me headers, so i was thinking of getting a pipe to replace the catalyc converter, but this guy was telling me that if i remove the cat. there will be no back preassure and eventually would cause long term damage to the engine, is this true or would the engine be fine if i remove the cat?
http://www.dezod.com/pd_random.cfm
#17
iTrader: (14)
Join Date: Jul 2004
Location: Las Vegas, NV
Posts: 3,120
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 272 hey dezod.. by putting a o2 sim on the sesor to get rid of the CEL... would the ecu also think that the gases being put out from the cat are correct... considering that emissions connects to the obd2 connector that reads the sensors u would think it would work.. i know they dont stick the reader thing in the exhaust like my truck.. so wat u think????
#20
Premium Member
Hey! Look At Me!! I'm a Supporting Member!!
iTrader: (4)
Join Date: Jan 2004
Location: Pembroke Pines, FL
Age: 39
Posts: 967
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 quick question,
right now I have a DC Header, OBX Hi-flow cat, and DC Sport TCS. with this on I wont pass emission right??? so if I replace it with random or stock cat, I will pass emission??? let me know
right now I have a DC Header, OBX Hi-flow cat, and DC Sport TCS. with this on I wont pass emission right??? so if I replace it with random or stock cat, I will pass emission??? let me know
#22
Registered!!
Thread Starter
Join Date: Aug 2004
Posts: 55
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 I've considered it now and my conclusion is that it simply isn't worth the hassle of switching it when testing and than getting caught once in a while with it for minimal performance...The engine is 1.7 4 cyl, and if you remove the cat you can't squeeze out that much diff. in HP or torque anyhow.
#23
7thgen Power Maker
iTrader: (74)
Join Date: Sep 2003
Location: Buffalo, NY, US
Posts: 9,048
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 0
Originally Posted by xproductionz
hey dezod.. by putting a o2 sim on the sesor to get rid of the CEL... would the ecu also think that the gases being put out from the cat are correct... considering that emissions connects to the obd2 connector that reads the sensors u would think it would work.. i know they dont stick the reader thing in the exhaust like my truck.. so wat u think????
As an experiment, I relocated one of the O2 sensors (the one normally below the header) to RIGHT BEFORE THE CAT on the new downpipe. The car threw CELS (delayed sensor reading from bank 1 sensor 1 & too rich bank 1 sensor 1). The sensor had a hard time reading and re-calibarting the mixture so my EGT's and A/F's were all over the board and real spuratic. The car would run UBER rich and suck *** for performance. I put it as close as I can get it to where it is nornally and BAM.....Everything stablizied. Think this was just from relocating. Imagine what eliminating would do?
GOD DAMN OBD2................I WANT OBD1 or OBD0 back!
Last edited by dezod; 09-01-2004 at 02:59 PM.
#24
iTrader: (14)
Join Date: Jul 2004
Location: Las Vegas, NV
Posts: 3,120
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 272 okay.. but i know the first sensor thats nearest to the head checks the a/f mixture.. but from my understanding the second o2 sensor reads the effectiveness of the cat.. which is where the sim would be put because its throwing the CEL.. correct me if im wrong.. i also did an experiment where i tried running the second o2 off the pipe and also removing it entirely..it doesnt affect my performance but it sure does throw a light??.. any thought or tests u could run
#25
7thgen Power Maker
iTrader: (74)
Join Date: Sep 2003
Location: Buffalo, NY, US
Posts: 9,048
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 0
Originally Posted by xproductionz
okay.. but i know the first sensor thats nearest to the head checks the a/f mixture.. but from my understanding the second o2 sensor reads the effectiveness of the cat.. which is where the sim would be put because its throwing the CEL.. correct me if im wrong.
#26
Registered!!
Join Date: Jul 2004
Location: nassau county
Age: 42
Posts: 236
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0
Originally Posted by xproductionz
okay.. but i know the first sensor thats nearest to the head checks the a/f mixture.. but from my understanding the second o2 sensor reads the effectiveness of the cat.. which is where the sim would be put because its throwing the CEL.. correct me if im wrong.. i also did an experiment where i tried running the second o2 off the pipe and also removing it entirely..it doesnt affect my performance but it sure does throw a light??.. any thought or tests u could run
Good questions.
about time someone responsed to this guy
#27
Registered!!
iTrader: (1)
Join Date: Jul 2003
Location: Southern Utah
Age: 39
Posts: 164
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 You guys are a bunch of idiots!!! If you take your cat off you are going to lose your bottom end power!! We are talking about a 1.7l 4 cyl. here!! They need back pressure!!! And to top it all off, removing the cat isnt going to give you any horsepower at all!!! You will lose HP!!! If you want to drive a fast car, then your first step is to sell your all show no go Honda!!!!!
#28
iTrader: (14)
Join Date: Jul 2004
Location: Las Vegas, NV
Posts: 3,120
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 272 why does everyone diss the civic when u guys drive one and bought one ur self... if ur gonna do that then why did u buy it **end rant** as for the removing cat and back pressure and stuff.... yea u loose alot of bottom end but gain high end.... basically makes daily driving suck but better for racing situations
#29
i dont really think its dissing our cars, its just being realistic. our cars are economy cars that arent meant to go fast. theyre meant to get from point a to point b, and get good mpg. thats it.
#30
iTrader: (14)
Join Date: Jul 2004
Location: Las Vegas, NV
Posts: 3,120
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 272 i know our cars are economy cars.. but hey.. we got people out there that want to up the ante a little and yet get turned down... i mean.. if someone wants to do womething to there car and it only adds 2hp....let them do it.. but lets say they do 5 things to the car that yields 2 hp a piece.. the that ups the ante at least 10 hp... this is just an example so i dont wanna be flamed for it... but i just gotta say lighten up a little... isnt that we are all here for.,.. to help each other out and not shut everyone down