Removing catalytic converter

[DPelletier]

Dean's right.

The '97 required a cat to meet the emissions regulations of the day (when it was built). The '98. 5 24v didn't need the cat to meet the same emission standards. I don't know about the California trucks, but the rest of the world didn't need cats on thier 5. 9's until the new reg's were implimented on Jan 1, 2004 (yesterday). 2003 California trucks had the cat and I also am unsure whether they had them there from 98. 5 - 2002.



Dave

 

[Forrest Nearing]

I don't see what a cat would actually DO on a diesel besides get clogged with soot



Forrest

 

[KL]

I don't what is involved with the new catalytic converter or the other new engine changes. But in a lot of new engines there are numerous sensors in the engine and/or exhaust system. So if something is not working normally it may effect other parts of the engines operation. So removing the cat may/may not always achieve the desired results IMHO. KL

 

[Forrest Nearing]

on modern gassers with additional O2 sensors located AFTER the cat, it'll throw a code, but they have O2 simulators that trick the computer to prevent the code...



but you can pretty much count on gaining performance every time you remove a catalytic converter... and that gain goes up exponentially with a turbocharged application



Forrest

 

[cannongeorge]

TMAN: I think from a California perspective, the CATS are being used to help meet upcoming CARB (California Air Resources Board) PM-10 (particulate) standards, as oppossed to NoX. These standards are brand new, and about to be adopted on a nationwide basis (in a few years).



The CATS are oxidation catalysts, made to "burn off" soot. This has been a difficult undertaking for engine manufacturers, as the proposed regulations (in California) change almost monthly. I think KL is correct, although you could remove it the potential for messing up existing engine controls is still there.



Steven M is correct, if the CAT is functioning correctly you shouldn't see any increase in backpressure. I doubt anyone will notice it. (I hope so!)



If anyone thinks this is bad, I'll be happy to forward the current and proposed NoX emission rules for residential water heaters... this is headed your way!

 

[cannongeorge]

Update on water heater emissions

I've already had inquirys about this topic:



I was mistaken in my earlier post, the new residential water heater regulations do not take place until Jan 2005:



The existing regulation (regarding water heaters) that is in effect now is:



On or after July 1, 2002, no person shall manufacture for sale, distribute, sell, offer for sale, or install within the South Coast Air Quality Management District any gas-fired water heaters unless the water heater is certified pursuant to subdivision (d) to a NOx emission level of less than or equal to:



(A) 20 nanograms of NOx (calculated as NO2) per joule of heat output (46. 5 lb per billion Btu of heat output); or



(B) 30 ppmv at 3% O2, dry (35 lb per billion Btu of heat input); or



(C) the emission limit specified in subparagraph (c)(1)(A) or (c)(1)(B) provided the manufacturer of the water heater meets the requirements of subdivision (f).



The future regulations



(3) On or after January 1, 2005, no person shall manufacture for sale, distribute, sell, offer for sale, or install within the South Coast Air Quality Management District any gas-fired water heaters unless the water heater is certified pursuant to subdivision (d) to a NOx emission level of less than or equal to:



(A) 10 nanograms of NOx (calculated as NO2) per joule of heat output (23 lb per billion Btu of heat output); or



(B) 15 ppmv at 3% O2, dry (17. 5 lb per billion Btu of heat input).



I am serious. Substantial penalties await those that violate this regulation. This is for Southern California only, but don't be surprised if this heads your way!



Diesel owners: wait until you see the lastest Diesel Engine Particulate (PM10) standards!

 

[EMD-Run8]

If I understand this right-------he likes diesels but doesn't like the smell? Hmmmmmmmm... ... ...

 

[ACerf]

Cat removed

For one thing who the heck thinks that removing at CAT it a federal crime! This is mandated by some states, of which California is one of them. This has nothing to do with the Feds. I asked my dealer about it, he told me unless you had an issue with exhaust system they would not even care! This will not void the warranty! If you are concerned just unbolt the CAT get the pipe that goes in its place and you are done. If you were to move to a state that did not have CATs on there trucks, and you registered the truck there. It would now be a truck from that state... with no CAT.

Also, the acticle in TDR said that the 325/600 would have a CAT but no EGR valve. But it would also have a full 4" exhaust.

 

[ACerf]

Cat removed

Removing the CAT will have no effect on the PCM or ECM. There are no sensors attached to the unit. And the CM's do not have any program associated with the CAT. It is not like a gas engine in that respect.

 

[Steve M]

Yeah, once the buzz wears off, it's just "smell". I bought my diesel to tow my 5th wheel and perform efficiently as I use it as a daily route vehicle with my job servicing elevators. I'm not fond of the smell of exhaust from any vehicle. Although castor bean oil in two-stroke dirt bikes smells kinda like food.

The problem with cats is low temperatures. Just like the flavorizer bars in the ol' gas grill, if you don't get the temperature up enough to keep them clean, they get all greased up and then you have a flare up and melt down of your steak. Too much idling or fuel additives aren't good for the cat. Since I run my trucks stock and work them hard every chance I get, a cat's not a problem for me. My '95 and '98 had one. Never had a problem with them and a co-worker used to comment on how the '95 never blew any smoke. But it smelled like any other diesel at idle.

My federal emissions equipped '03 doesn't have a cat. Our state follows the federal mandated standards and doesn't have additional state mandated standards. The common rail injection with pilot capability cleans up the exhaust enough to not require a cat.

 

[Stroker Smoker]

If You are woried about the cat but don't want to get busted by any government for removing it the solution is simple: Cut the exhaust pipe behind the converter, remove some of the exhaust hangers behind the cat so the remaining exhaust pipe isn't in the way of the new cut in the pipe, next take some re-bar or a small spud bar and a hammer and proceed to break up the guts in the converter. You may have to start the truck up a couple of times blow out the cat guts. After it is completely gutted use a MIG welder and reweld the cut pipe or go to NAPA and buy a 4" exhaust coupler and muffler clamps. And reinstall all exhaust parts.



This will allow your exhaust to flow better (but not as good as a straight pipe) and still give the appearance of the converter being there.



The modification will not affect the ecm or OBD in any way



Phill

 

[ACerf]

Cat removed

Ok, here is another question. Lets say we don't remove the CAT but instead lets remove the Muffler! Will the CAT alone make the monster quite enough and more powerful. And legal for those who seem to have the governments interest at heart.