disadvantages of going catless

[RAZR]

im gunna need a new exhaust nose to tail so i wanted to ask what are the pros and cons of going catless?
and anyother tips i should know?

[Tdurr]

emissions. besides that, none.

[RAZR]

emissions. besides that, none.

i dont have emissions in IL

will it make my exhaust like a million times louder on this car?

i also remember seeing on this site that 2.5 in exhaust is perfect for this motor is that correct??

[lostforawhile]

I just built an entire system out of 2 inch, you don't want to go to big or you will lose exhaust velocity and scavenging. even this new S&S header uses 2 inch pipe after the collector

[RAZR]

I just built an entire system out of 2 inch, you don't want to go to big or you will lose exhaust velocity and scavenging. even this new S&S header uses 2 inch pipe after the collector

so what ur saying is that i should go 2in pipe for best results?

[lostforawhile]

so what ur saying is that i should go 2in pipe for best results?

it's debatable, some say 2.5 some say 2, everything i've seen says a 2 inch system is good for this displacement engine, it also depends on what kinds of bends you use, if you use crimped over bends, like most exhaust shops do, you might go to 2 and a half, because you will have restrictions in the bends, I used mandrel bends so I don't have to take that into account

[RAZR]

it's debatable, some say 2.5 some say 2, everything i've seen says a 2 inch system is good for this displacement engine, it also depends on what kinds of bends you use, if you use crimped over bends, like most exhaust shops do, you might go to 2 and a half, because you will have restrictions in the bends, I used mandrel bends so I don't have to take that into account

so in ur opinion should i go catless?? or get a high flow cat?
or just keep the stock one?

[lostforawhile]

so in ur opinion should i go catless?? or get a high flow cat?
or just keep the stock one?

thats up to you, if you decide to keep it, definitely go with a high flow cat, i'm sure the stock one is pretty restricted by now

[RAZR]

thats up to you, if you decide to keep it, definitely go with a high flow cat, i'm sure the stock one is pretty restricted by now

so if i go catless my car isnt gunna be throwing codes or the check engine light? ill just throw black sut out the back all the time right?

[lostforawhile]

so if i go catless my car isnt gunna be throwing codes or the check engine light? ill just throw black sut out the back all the time right?

you shouldn't be throwing soot out the back at all, cat or no cat, and you won't get a check engine light, these are pre obd1, only obd2 cars have the extra o2 sensor after the cat

[A18A]

your car is worth less without it cause the cat has precious metals inside

[AccordB20A]

Yeah just get a system made without the cat and youll be sweet.

[Hauntd ca3]

if you can get away without it, do so.
2.25 inch is the perfect compromise for piping.
to get rid of the kight if you dump the cat, cut the wire at the cat temp sensor and crimp a ring terminal to the end of the wire and bolt it to earth.
the cat temp sensor is just a bi metallic switch that goes open circuit when its to hot.
putting it to ground make it think its fine all the time

[MessyHonda]

yeah go catless..i have a straight pipe and now the car has more room to breath

[Nafs Asdf]

if you can get away without it, do so.
2.25 inch is the perfect compromise for piping.
to get rid of the kight if you dump the cat, cut the wire at the cat temp sensor and crimp a ring terminal to the end of the wire and bolt it to earth.
the cat temp sensor is just a bi metallic switch that goes open circuit when its to hot.
putting it to ground make it think its fine all the time

Cat temp sensor? I didn't know these cars had that. And assuming kight means light, which light would that be?

[lostforawhile]

if you can get away without it, do so.
2.25 inch is the perfect compromise for piping.
to get rid of the kight if you dump the cat, cut the wire at the cat temp sensor and crimp a ring terminal to the end of the wire and bolt it to earth.
the cat temp sensor is just a bi metallic switch that goes open circuit when its to hot.
putting it to ground make it think its fine all the time

I don't think the USDM cars have the cat over tempreture warning light and sensor

[frantik]

im gunna need a new exhaust nose to tail so i wanted to ask what are the pros and cons of going catless?
and anyother tips i should know?

pros: you're not polluting as much
cons: you don't get as much power

[RAZR]

pros: you're not polluting as much
cons: you don't get as much power

yeah well i just found out that if i remove my cat theres a 2500 fine

:(

[Hauntd ca3]

most cats i've come across have a sensor poking out the side of them
they are there so if the temp gets to high it'll let you know.
as cats get clogged up they get hotter which can end up in the carpets catching fire.
the light on the dash looks like a wee straight through muffler with some wavy lines above it.

[Vanilla Sky]

Just get a high flow cat. They're not very expensive, and won't cost yo more than 1 or 2 HP. If you're really concerned with 1 or 2 HP, then you are probably replacing your air filter every oil change and using $10/qt race oils in your 120 HP motor.

As for exhaust size, go with a 2.25 inch pipe. If you go any more, you're not going to scavenge well, and if you go smaller, you're going to have issues flowing enough in the upper RPMs. I'm assuming you'd rather more top end power at the expense of torque down low.

[AccordB20A]

another way to shut the light on the dash up is to simply unplug the box under the seat :)

[frantik]

yeah well i just found out that if i remove my cat theres a 2500 fine

:(
that is a definite con :-p

[Vanilla Sky]

It is a federal offense to tamper with emissions control devices. While the law is intended to shut down shops that bypass emissions systems, it can be applied to an individual.

The most I've ever heard come from it is a fix-it ticket.

[Nio]

pros: you're not polluting as much
cons: you don't get as much power

Last I checked having a cat removes pollution not adds to it
and removing it gives HP not takes it away.

I remembering gaining half a second pulling my off my 03. Civic In the 1/4

[frantik]

Last I checked having a cat removes pollution not adds to it
and removing it gives HP not takes it away.

I remembering gaining half a second pulling my off my 03. Civic In the 1/4

yes, i posted the pros and cons of having a cat, not removing it, you're right

[AccordB20A]

over here where we have to "certify" engine swaps in our cars we pretty much have to have a cat in the exhaust or it wont pass the cert. Best way around that (all my mates have done it) is to smash the shit out of the inside of the cat and then its just a straight thru pipe pretty much. But in your case where your getting a new system made, just get one of those "high flow" cats, then if the law ever comes knocking your safe.

[RAZR]

over here where we have to "certify" engine swaps in our cars we pretty much have to have a cat in the exhaust or it wont pass the cert. Best way around that (all my mates have done it) is to smash the shit out of the inside of the cat and then its just a straight thru pipe pretty much. But in your case where your getting a new system made, just get one of those "high flow" cats, then if the law ever comes knocking your safe.

Well I decided not to get a full exhaust cause he quoted me way to much than I can afford so I decided to go the cheap route and just get the cheaper stuff
But I am gunna have a flow master muffler put on the back

[Vanilla Sky]

The Pacesetter kit isn't bad, just oversized with a marginal muffler. I have one, and it really wasn't all that bad.

[SkateK610]

Im by chicago too and I dont have a cat, sound wise you only get some extra noise at rpms over 3.5k but for crusing your fine.

[RAZR]

Im by chicago too and I dont have a cat, sound wise you only get some extra noise at rpms over 3.5k but for crusing your fine.

yeah but the exhaust shop wont let me talk it off and also my dad wont let me take it off. and because i live under his roof what he says goes
:( :( :(

[stat1K]

but see gutting a cat is stupid since you can sell one to a scrapper for like 100-150 out here... lol.

[AccordB20A]

we can sell the gutted material over here i believe.

[lostforawhile]

around here, no one really cares on these old cars, they are exempt all over georgia once they reach 25, driving my car on the weekends to enjoy it is not going to have much of an impact on the enviorment, mowing my lawn produces more pollution, there aren't enough of them on the road to even have a measurable impact. They do need a gross polluter law though, if you are driving a car that looks like a mosquitto fogger, get the pile of junk off the road. We have a few like that around here, you can't see the car due to the smoke. it's how many miles per gallon of oil. as far as the size of the exhaust, if you are running good mandrel bends, you will probably be just fine with 2 inch pipe

[ecogabriel]

around here, no one really cares on these old cars, they are exempt all over georgia once they reach 25, driving my car on the weekends to enjoy it is not going to have much of an impact on the enviorment, mowing my lawn produces more pollution, there aren't enough of them on the road to even have a measurable impact. They do need a gross polluter law though, if you are driving a car that looks like a mosquitto fogger, get the pile of junk off the road. We have a few like that around here, you can't see the car due to the smoke. it's how many miles per gallon of oil. as far as the size of the exhaust, if you are running good mandrel bends, you will probably be just fine with 2 inch pipe

:lol: :lol: :lol:

True; mine got its last emissions test EVER May 2010!!! Clean and sweet!

All the rest is very funny -and true!


:lol: :lol:

[Vanilla Sky]

The issue is that everyone thinks the same thing. Add it all together and it gets hard to breathe.

[lostforawhile]

The issue is that everyone thinks the same thing. Add it all together and it gets hard to breathe.

you forget most cars this old don't get driven much, the overall amount of pollutants goes way down, just by the number of much fewer miles being driven, it's all irrelevent anyway, China dumps more polluntants in the ai in a week, then the entire state of Califonia did in the smog days of the 70's, in a year.

[Vanilla Sky]

Where did you get your stats? I'm betting they came from a very dark and smelly place.

[Nio]

Where did you get your stats? I'm betting they came from a very dark and smelly place.


After camping for the last 3 weeks I have some pretty dark and smelly places.


as for what hes saying,I do agree, now adays all the kids seem to want new cars..In texas its hard to find anyone driving a import unless its someone old or some major enthusiest.

[lostforawhile]

Where did you get your stats? I'm betting they came from a very dark and smelly place.

it's very well documented what the Chinese dump in the air every day, they are a communist state, there is no kind of enviormental control whatsoever,
it's all about more and more and more production, what goes into the air, or the water or the ground, is of no concern to them. It's also a fact that older cars that are driven for pleasure do not contribute in a significant way to the pollution problem, the cars that do most of the polluting, are the ones that aren't maintained or tuned up, the junkers people drive until they quit in other words

[Vanilla Sky]

...the junkers people drive until they quit in other words

You mean 90% of the cars on the board?

Did you also know that China is the leading producer of solar cells, and they employ more green tech than we do? They realized that green is where the money is, so they do as much as they can to be green in order make more money.

They're not Communist like you're describing. They're almost every bit as capitalist as we are. There are longer lines for food in the US than there are in China.

Just because there are no laws against dumping toxins doesn't mean that they do. On the flip side, just because there are laws against dumping toxins doesn't mean it happens all the time in the US.

Facts, check them.

[lostforawhile]

You mean 90% of the cars on the board?

Did you also know that China is the leading producer of solar cells, and they employ more green tech than we do? They realized that green is where the money is, so they do as much as they can to be green in order make more money.

They're not Communist like you're describing. They're almost every bit as capitalist as we are. There are longer lines for food in the US than there are in China.

Just because there are no laws against dumping toxins doesn't mean that they do. On the flip side, just because there are laws against dumping toxins doesn't mean it happens all the time in the US.

Facts, check them.if you dislike these cars so much, why are you even here? most people on this board care about their cars and take care of them, many buy them as junk and spend a lot of time fixing them back up

[Vanilla Sky]

Way to interpret things wrong, dude.

[lostforawhile]

this is why I don't spend much time here anymore, I happen to care about these cars and have spent untold hours trying to help people on this board with them, most of the cars on this board are not junkers

[Vanilla Sky]

Most of the cars here are. The average new member is here to find a fix to keep the car going for another 500 miles.

It's how it is right now.

[frantik]

there aren't enough of them on the road to even have a measurable impact.

here an san jose there are a LOT of 3geez on the road.. i WISH we could have no smog after 25 years but that would leave tons of old cars which are likely to be bad polluters on the road.

[lostforawhile]

here an san jose there are a LOT of 3geez on the road.. i WISH we could have no smog after 25 years but that would leave tons of old cars which are likely to be bad polluters on the road.

there seem to be a lot in cali, out here you rarely see one. I think there are pockets of them across the country, but overall they are spread pretty thin

[Vanilla Sky]

I think they just sold a ton more in Cali, so there are more left out there. They also have a much different car culture there. I wish I could get my hands on some of the old Japanese iron that they have in Cali that never caught on in the South.

[SkateK610]

Reason out west they have more of the older cars running is because of(the lack of) SALT!

[Vanilla Sky]

No salt down here. Imports just didn't sell as well in the 80's as Domestics.

[forrest89sei]

I see many 3G's where I live, but I also live in one of the Rare Counties in California that you only smog if you transfer title.

Get a P.O. BOX In Tuolumne County and forget about smog lol

[RAZR]

Reason out west they have more of the older cars running is because of(the lack of) SALT!

i hate salt so much. 90% of all the problems on my car is because of the fucking SALT!!!!!!!!!!!!!!!!!!!!!

[import racer]

Salt on the roads sucks,wish they didn't use it around here and our cars would last longer!

[lostforawhile]

what they used to do was spray the crap out of the bottom of the car with used motor oil, the dirt would stick to it, and form a protective nasty layer, but it really worked, they used to do it commercially at a lot of stations until the epa banned it being done for money. it was very common, best rust protection ever, in the summer it gets power washed off,sometimes the entire rear quarters were sprayed, looked terrible during the winter, but better then rust holes. This is why if you find an old rusty car with a bad oil leak, often the area under the oil won't be rusted. another product is LPS 3, it's a waxy anti corrosion coating, you can spray it in all the seams under the car every year, it's very very good, floatplane pilots live for the stuff, they spray every bit of fuselage they can to protect it from salt spray, i use it at work to coat freshly machined parts, it's nasty tacky stuff but boy does it stop rust http://site.skygeek.com/yswimages/lps00316.jpg

[Hauntd ca3]

you can get stuff out of the uk called waxoil.
comes in a big container with a spray lance so you can get right in to the sills and pillars and frame rails.
as for the under floor, good old bitumanised underseal works for me

[Dr_Snooz]

I've heard good things about Por15. Haven't used it myself though.

[88lxi-shortram]

I've used por15 cleaner in a gas tank before and it worked amazingly

[Vanilla Sky]

I can certainly attest to oil keeping your car rust free. Look at any Jeep that has an oil leak (which is most of them). You'll see where the oil has built up is nice and clean, but where the oil stayed away from is rusty.

[lostforawhile]

you can get stuff out of the uk called waxoil.
comes in a big container with a spray lance so you can get right in to the sills and pillars and frame rails.
as for the under floor, good old bitumanised underseal works for me

thats pretty much the same thing as the Zep LPS 3, really good stuff, it's a wax based coating,blocks air and moisture from the metal, without those you don't get rust

[RAZR]

not to change the subject of rust prevention but
i got my car back today and it ended up at 375. the exhaust guy decided to go witha full 2in cat-back exhaust, got a flowmaster on the back and got the flex pipe fixed on the front. i am very happy except it is sooooooooooooooooo quiet in my car its weird. but i can tell the difference it accelerates faster and it revs alot smother :)

[Vanilla Sky]

I wouldn't be at all surprised if your old muffler was collapsed. It's much more common than you'd expect.

[RAZR]

I wouldn't be at all surprised if your old muffler was collapsed. It's much more common than you'd expect.

yeah it looked pretty bad when my dad gets home i can get the pics from him cause there on his phone
but the entire bottom pan of the muffler was hanging down :lol:

[cygnus x-1]

what they used to do was spray the crap out of the bottom of the car with used motor oil, the dirt would stick to it, and form a protective nasty layer, but it really worked, they used to do it commercially at a lot of stations until the epa banned it being done for money. it was very common, best rust protection ever, in the summer it gets power washed off,sometimes the entire rear quarters were sprayed, looked terrible during the winter, but better then rust holes.


That is a great idea! My Prelude doesn't go out in the winter but my truck does.

Only thing is, here in Chicagoland we have super incredible ninja salt. That stuff can get through anything and you can almost hear it rusting out your wheel wells.


A couple years ago I de-catted the Prelude and took the core to the scrap yard. The guy looked at it funny and said something like, "Wow, that's an old one." I got $10 for it; which is $10 more than I had before.


Recent research on exhaust sizing has led me to believe that all of the exhaust scavenging to be had occurs at the collector and in the primary tubes. Beyond that the sole function of the exhaust piping is to route the gas to the back of the car. So as long as it's *big enough*, it's fine. 2" with mandrel bends would be big enough unless you have some serious mods.

C|

[DBMaster]

I used LPS3 for the two years I lived in Corpus Christi. 1992-1994. Still no rust. LPS3 and frequent hand washings with thorough hosing helps. Hard to do when it's cold out, though.

[RAZR]

cygnus what area of chicago do u live?