4x4runner

A recent mud trip FUBARed my exhaust, since I gotta drop some cash on it anyways, I was wondering if anyone has tried clearing out the cat ( like running a broom stick through it). Any performance or sound gains?

2001Millrunner

I've done it before on my 92 Honda Prelude, trust me, you do get some hp gains but its not worth smelling unburnt toxic fumes everytime you sit still with your engine on. not to mention the nausiation. that honeycomb thing inside the cat is not easy to knock off unless you have some airtools(kinda like a miniture jackhammer) is what i used. I still passed emissions(by about .01) and what not but still i would NEVER go back to that again.

gwhayduke

It still amazes me that people want to gut their Catalytic converters and release all those unburned hydrocarbons into the air. Evidently you don't remember how badly cars stunk prior to their use. El Paso has some of the worst air in the nation due to the unfettered exhaust of cars in our sister city, Juarez, Mexico. Practice a little responsibility to someone other than yourself.

rimpainter.com

Go with a high flow cat.

zamboni95

High flow cat is the way to go.

Downey has a header / high flow cat / muffler set-up that will cost you apprx $550. Easy to put on yourself.

Churnd

I second that. I ran without one for a while, and hated it. The truck just didn't run right.

TDiddy

There ya go.

keisur

you got a link for this kit or do I have to order it straight from Downey and call and get a price quote?

zamboni95

I would give Downey a call. Or you can order from truck performance. Here's a link to the Headers. I looks like v6's are a little more expensive.

Downey site: www.downeyoff-road.com

Truck Performance Header (I didn't see the Downey exhaust for your application on this site, call Downey):
http://www.truckperformance.com/vehi...UNNER&sf4=3.4L

I would order direct from Downey.
Not sure if they have the same set-up for your application as mine, but I am sure they would be able to help you out.
You may not even need the above headers. Downey may have bolt on cat-back system that would work for you. Just guessing right now, because I left my catalog at home. If you need more information just let me know and I can check the catalog later on tonight.


Cheers

Bumpin' Yota

I have a hiflow cat on right now - go that route trust me.

keisur

so all you have is a high flow cat and stock exhaust and headers?

EDIT: nevermind, I just read the fine print at the bottom of your sig. :pat:

Zubaltec

I don't have a cat and have never had one on any of my cars, and I love it. Someone else posted a couple of weeks ago on how they did research on this issue in school and found that not running a cat doesn't hurt the enviroment as much as you think. Another person posted that they passed emissions with out a cat. Just my .02.

Thanks,
John

rimpainter.com

Yeah I am sure that "some guy that did research at school" is more credible than the entire staff and research department at the EPA.

Bumpin' Yota

Stock exhaust for now outside of the hiflow cat. The exhaust and o2 sensor is next then **shudder** headers. But I was just trying to convince the original poster not to "broomstick" the old cat.....

But Dr Z has me thinking...

gwhayduke

Bravisimo 96!

Isn't it amazing how often he said/she said anecdotes masquerade as science.

Zubaltec...
Try mixing your interest in speed with reduced exhaust emissions, increased power and gas mileage using legal methods. The holy grail of the IC engine. You probably have access to an emissions test machine and a dyno since you're in motorsports. Dyno your 4Runner with and without cat while testing emissions. I'd love to see some data on that! Then we can talk about breaking the law.

Dr. Zhivago

What'd I do now???

Dr. Z

keisur

I pass emissions everyday usually after mexican food or a night of drinking alot of draught beer, and I don't have a cat either, I have three dogs though.

paxam

One of my friends gutted the cat .the truck ran stronger but got worse mpg. the O2 sensors got cooked . he had to replace the cats and O2 sensors now the truck runs great.

Zubaltec

Why would I waste my time to prove to you what I already know. I had the cat on my truck when I first put the headers and exhaust on and I was very disappointed. I took the cat off and now it feels like I got my moneys worth. So why don't you do some more research on emissions for me. Use you hands for typing and find some information besides some cop out that the EPA knows more then some guy, cause I got use mine to get back to building 600-1000 HP Supra's without cats.

Thanks,
John

rimpainter.com

That was just the educated response I expected from you.