catalytic removal

gty · 09-28-2008, 06:53 PM

Any side effects, good or bad, in removing catalytic converter on 1982 928? What should be done with the oxygen sensor? It is before the cat converter. Also,, anybody know who sells a catalytic "test pipe" to replace the converter?/ Thanks very much.

Danglerb · 09-28-2008, 10:24 PM

O2 sensor is used to accurately set the air fuel mixture, you need to have one in good working condition.

Catalytic converter removes about 90% or more of the harmful emssions. The factory cat was old technology and lost about 10 hp. Modern cats have far less resistance, 1 or 2 hp, maybe less when you consider they allow a freer flowing muffler without being as loud as the same muffler without cats. Running without cats is socially irresponsible, and your exhaust will stink.

gty · 09-30-2008, 06:00 PM

thanks very much for the repy

surfdog4 · 09-30-2008, 06:35 PM

if you do some searches on here, you can find folks that make and sell a "y" pipe that accomodates the O2 sensor and eliminates the cat. I don't necessarily think it is irresponsible to eliminate the cat..if it is legal in your state then so be it.

In my state, if you register the car as "historic" you do not have to be emissions tested..but you are also not supposed to use the car as a daily driver

..P · 10-28-2008, 10:01 AM

On one hand I agree with the "socially irresponsible" comment, but on the other hand, driving a car that gets this kind of gas milage, goes this fast, and is ostentatious by some standards, could also be deemed "socially irresponsible". Since I don't even know what fork to use, and have been on the socially irresponsible side of the automotive coin for many years (what else could you call owning a TVR?) being called "socially irresponsible" could actually be a badge of honor. I hope my sense of humor is recognized for what it is!

And now.............where can I get a cat that will bolt onto my 1983 S and give me 8 more horsepower! (Please don't send a K&N air filter guy to do a mans job)

m21sniper · 10-28-2008, 11:02 AM

Quote:

Originally Posted by gty

Any side effects, good or bad, in removing catalytic converter on 1982 928? What should be done with the oxygen sensor? It is before the cat converter. Also,, anybody know who sells a catalytic "test pipe" to replace the converter?/ Thanks very much.

I have a 928 Specialists test pipe in my 928 (and a full race exhaust behind it). It is definitely good for 10-15hp and a sizeable weight loss of maybe 30lbs or so.

Click the link below in my signature to hear my beast.

m21sniper · 10-28-2008, 11:03 AM

Quote:

Originally Posted by Danglerb

Running without cats is socially irresponsible, and your exhaust will stink.

To hell with society.

PS: My exhaust doesn't smell any different at all since i took the cat off.

Dean_Fuller · 10-28-2008, 11:06 AM

I removed mine on the 89 S4 and added Rogers X pipe....I also removed the muffler resonators and replaced with single mufflers in that area and removed the rear muffler and added a RMB.....That said I agree with Danglerb...the exhaust stinks and is really over powering ...I will be adding high flow cats to the system to fix that and quite it down a bit.

I suggest using high flow cats...even if you state doesn't require it...they could soon.

m21sniper · 10-28-2008, 11:11 AM

Well yeah...if you put a full race exhaust on like you did it's going to sound like a race car.

(did i mention to click on my link? Hehe)

Dean_Fuller · 10-28-2008, 11:24 AM

Yeah....I hear ya m21sniper.....my sons think the "new exhaust" was cool.....Just a tad too loud for me. One of their friends that heard it said it sounds like a race boat at idle. The extra DB's I think have actually starting to make some of the trim pieces vibrate and rattle...who knew!

BTW...cool video.

Dean_Fuller · 12:45 PM

Quote:

Originally Posted by m21sniper

To hell with society.

PS: My exhaust doesn't smell any different at all since i took the cat off.

I wonder why some cars exhaust will stink and others will not???? I wonder if mine maybe is running rich????

porken · 10-28-2008, 02:58 PM

I don't like the smell of catylized exhaust!

If your non-cat exhaust smells bad, you probably have an ignition and/or fueling problem. Especially a 32V.

My (well tuned) '86.5 with X-pipe puts out mostly water vapor with little odor.

Dean_Fuller · 10-28-2008, 07:44 PM

Quote:

Originally Posted by porken

I don't like the smell of catylized exhaust!

If your non-cat exhaust smells bad, you probably have an ignition and/or fueling problem. Especially a 32V.

My (well tuned) '86.5 with X-pipe puts out mostly water vapor with little odor.

Ken,
Mine shows NO faults on the HAMMER.....Where do I go to see whats not right???

Danglerb · 10-28-2008, 09:11 PM

Maybe its just a poor sense of smell? or personal sensitivity.

rhjames · rhjames's Garage

Quote:

Originally Posted by Danglerb

Maybe its just a poor sense of smell? or personal sensitivity.

anything like hygene (that would be personal, wouldn't it.....)

--Russ

Danglerb · 10-29-2008, 12:14 AM

Smell could be related to brand of gas and additives too.

Funny comments deleted since you know what I meant anyway.

Dean_Fuller · 10-29-2008, 09:29 AM

Ruff crowd

Its definitely a stronger exhaust smell then WITH the stock cats.

m21sniper · 10-29-2008, 10:14 AM

Quote:

Originally Posted by Danglerb

Maybe its just a poor sense of smell? or personal sensitivity.

It's also possible that i can't smell a difference post cat removal because my old cat may have been whooped, and was no longer doing what it was supposed to.

Danglerb · 10-29-2008, 11:06 AM

Quote:

Originally Posted by m21sniper

It's also possible that i can't smell a difference post cat removal because my old cat may have been whooped, and was no longer doing what it was supposed to.

We have two cats like that, never do what there supposed to, lay around not catching mice. They don't smell too good either, but we haven't tried a cat converter on them yet.

Dean_Fuller · 10-29-2008, 11:09 AM

tastes like chicken....I hear.