BeeFly

I have a 98 civic EX just getting broken in at 194k. Muffler fell off behind the rear flange due to Michigan Road salt induced rust. I bought a Stainless Steel cat back exhaust by Yonaka, all 2.362" diameter pipe (60mm). I went to put it on and found that my resonator pipe had rust welded itself to the catalytic converter. Now I need to replace the Cat. The nice thing about Michigan is we have no emissions laws and it is legal to run without a Cat. On the back of the Catalytic Converter piece there is a port for the secondary/downstream O2 sensor, so I need something that has a port for the secondary O2 sensor.

My aim in this project is to stay as close to stock quiet as possible, more durable exhaust, maintain low end torque, and get better gas mileage. Not really looking for more high end performance, but if I get it I am not complaining

I am on a budget so here is what I have found
Spec D high flow catalytic converter 2.367" inlet 1.998" outlet $32
K2 high flow catalytic converter 2.367" inlet 1.998" outlet $35
Invidia test pipe 2.362" diameter $49

Questions
I am assuming that the pipe coming in off the manifold is 2.367" is this correct?

I dont like the idea of two inches of my exhaust being 2" pipe at the back side of the cat when the rest is 2.367" how much will this hurt my gas mileage?
I also dont like the idea of running catless, pollution/noise, but here is my question would gasses getting to my secondary O2 sensor after running only through a test pipe and not a cat affect my engine performance, gas mileage, or tune?

If anyone has any better suggestions of BOLT ON catalytic converters that have both a 2.362" inlet and outlet for less than oh say $80 let me know.

Also I am obviously replacing the secondary O2 sensor, what are your suggestions on what O2 sensor to get?


I need to order something fast as I already have a fix it ticket.

BlueEM2

iTrader: (1)

I will never recommend running without a cat. Emission tests or not you will pollute like crazy.... At least get a high flow like Random Tech for 300 bucks so you will somewhat filter your exhaust.

I don't understand why so many people think it's okay to run without a catalytic converter just because they have no emission testing.

You will throw a check engine light with this setup unless you do the o2 simulator trick.

BeeFly

I cannot afford $300. I am looking to fix it cheap
What do you think of these 2 cats
http://www.k2motor.com/92-00-honda-c...converter.html
http://www.specdtuning.com/mhf-cv92.html
Or do you know of one with both a 60mm inlet and outlet CHEAP

also o2 sensor opinions?

BlueEM2

iTrader: (1)

Those probably won't filter anything... but it doesnt matter.. 300 isnt a whole lot to have it fixed properly. An OEM cat is 1000+

GolNat

iTrader: (7)

A cheap cat isn't going to last long or filter anything. There expensive because of the precious metals that are in them. If you don't have the money save up.

OEM (Denso) o2 sensor.

BlueEM2

iTrader: (1)

Agreed. I wish Kenny would chime in here. He is a polluter too

BeeFly

Don't worry I went with ordering the cat. I don't like the idea of polluting either. By the way a catalytic converter doesn't "Filter" anything, and if it does you have serious trouble.

Kennykid2002

iTrader: (1)

Hey, I recycle :3

BlueEM2

iTrader: (1)

A catalytic converter doesn't clean the exhaust?

Kennykid2002

iTrader: (1)

It uses chemical reactions to reduce output of the harmful pollutants into stable (less) harmful components.
As you know, your car produces CO2 (Carbon Dioxide) and H2O (Water) in the process of burning fuel.
That is nice in all in a perfect world scenario; but as you know, we do not live in a perfect world.

As you know, fuel is primarily based on crude oil created by organic matter...
The burning of such fuel also produces other harmful organic gasses, including NO (Nitrous oxide) and CO (Carbon monoxide, like in the burning of charcoal); which are poisonous to human health.

So technically, a "Catalytic converter" doesn't "filter" anything.
It's main function is function is exactly what it's named for. (Surprise surprise!)
It uses a "catalyst" (precious metals) in a chemical reaction to "convert" those harmful exhaust gasses into less harmful emissions.

Those precious metals are what makes the kitty so expensive.


Sorry for going all nerd-mode on you guys, thought I'd explain it.
I still run a testpipe because I'm a ricer.

BlueEM2

iTrader: (1)

Bah... I understand why it's called a Catalytic "Converter". I still consider it a filter hahaha