Catalytic convertor upgrade advise...

LocoCRD · **Posted:** Wed Sep 05, 2007 3:20 pm

Have a guy at work that put a high flow coverter on his power stroke along with a full exhaust. He swears it made a big difference. He gave me his old convertor which is a 3" inlet and outlet. I'm thinking of putting it on the crd and going 3" back from there. Any thoughts on whether or not this would be worth the trouble? Thanks in advance.

Dennis

DarbyWalters · **Posted:** Wed Sep 05, 2007 4:30 pm

http://ect.jmcatalysts.com/technologies-diesel-no2.htm

http://www.dcl-inc.com/prod2.cfm?autoid=107&lg=EN

A couple of sites with some good information. 3" might be a bit large.

nix · **Posted:** Wed Sep 05, 2007 5:02 pm

On a turbo car the bigger the exhaust the better. I know many people that run 3.5" full turbo-back exhaust systems on 2.0 liter 4 cylinders (gasoline) and they make the highest HP/torque numbers over 2.5" and 3" systems. Also the turbos would spool quicker and thus the hp/torque came on sooner. I wouldn't even consider upgrading my exhaust unless it was at least 3". Of course.. I'd do a high-flow cat or no cat.

You should gain HP with a 3" system even using the Ford's cat. I'd personally just get a high-flow 3".

Sir Sam · **Posted:** Wed Sep 05, 2007 6:18 pm

LocoCRD wrote:

Have a guy at work that put a high flow coverter on his power stroke along with a full exhaust. He swears it made a big difference. He gave me his old convertor which is a 3" inlet and outlet. I'm thinking of putting it on the crd and going 3" back from there. Any thoughts on whether or not this would be worth the trouble? Thanks in advance.

Dennis

All the backpressure an engine needs to provided by the turbo, everything after that is just restrictive.

TDI4BY · **Joined:** Sun Apr 02, 2006 11:56 pm **Posts:** 644

A gasser cat is not the same either as far as I know. Diesel specific cats are $$$

McMoney · **Posted:** Fri Sep 07, 2007 1:12 pm

I had cut the cat and muffler out and it did make a noticeable inprovement on the amount of power it spooled faster, but was very loud :twisted:

But due to municipal bylaws that came into effect i have now reinstalled a muffler. It is a dynomax #17513, they have a kit for the crd but it is only a 2.5 inch. I dont think i need a cat, but if i did i would have gone with a 3 inch one and a whole 3 inch exhaust.

LocoCRD · **Posted:** Fri Sep 14, 2007 9:00 pm

Well I finally went over and got the cat that came off the power stroke. Holy smokes is it big. I was told it was a 3" inlet/outlet but it is more like 3.5. I will have to climb under the jeep and see if there is even room for that beast under there. I bet it would flow alot more than the stock one though.

chrispitude · **Posted:** Sun Sep 23, 2007 7:01 pm

So has anyone actually put a 3" cat-back exhaust on a CRD? How does it drive, and how does it sound? I am looking for more power, but not for something obnoxiously loud.

- Chris

brew1 · **Posted:** Sun Sep 23, 2007 7:22 pm

chrispitude wrote:

So has anyone actually put a 3" cat-back exhaust on a CRD? How does it drive, and how does it sound? I am looking for more power, but not for something obnoxiously loud.

- Chris

Unless your state requires emissions testing for diesels, why not delete the cat and just go with a high flow muffler?

chrispitude · **Posted:** Sun Sep 23, 2007 7:27 pm

brew1 wrote:

Unless your state requires emissions testing for diesels, why not delete the cat and just go with a high flow muffler?

Hi brew1,

I don't know what the PA diesel emissions laws are. The all-important questions still apply - what's the gain, and is it as quiet (or nearly so) as factory? This is my wife's daily driver and I don't want to turn it into a good ol' boy rig. I would like to get some more towing power out of it though.

- Chris

brew1 · **Posted:** Sun Sep 23, 2007 7:34 pm

chrispitude wrote:

brew1 wrote:

Unless your state requires emissions testing for diesels, why not delete the cat and just go with a high flow muffler?

Hi brew1,

I don't know what the PA diesel emissions laws are. The all-important questions still apply - what's the gain, and is it as quiet (or nearly so) as factory? This is my wife's daily driver and I don't want to turn it into a good ol' boy rig. I would like to get some more towing power out of it though.

- Chris

Faster turbo spool up and lower EGT's. Not sure about hp or torque gains.

gmctd · **Posted:** Sun Sep 23, 2007 7:56 pm

It would be lots louder, fer sure

Diesel 'cats' are very different from gasser (patooie!) units, which are really catalytic convertors, with platinum element - Diesel units are usually oxidation convertors, or soot traps, where the ceramic honeycomb has no rare earth element, but is merely there to trap the black soot - when you hit the hiway for awhile, the ~625degf exhaust gasses heat the honeycomb, which then burns off the trapped soot, creating relatively harmless ash which exits with the exhaust gasses - do a search on ash, and the human lung

Most states have lenient Diesel inspections today, but that will likely change in '08 because of congress' sudden interest in Green technology, global warming, and all those idiotic Diesel owners that think it's cool to blow billowing black smoke everywhere they go - not only that, but your state is not eligible for federal hiway funding if they don't comply with federal emissions standards, which require state vehicle inspections, controlled from computers at state DOT centers - you drive onto the dyno, the guy (or gal) plugs into the on-board ALDL connector, and a remote robot runs your truck thru it's paces, shuts it off, and a local printer starts reeling off paper indicating parameters passed, parameters failed, and your name logged in DOT databases as a vicious polluter

Oh, yeah - it's comin' - smog cops knockin' on yer doors in the middle of the night, jammin' tracker devices up yer noses, confiscatin' Diesel vehicles and driver licenses - guess who's watchin', even now.......readin'..........takin' notes........makin' lists........................

gmctd · **Posted:** Sun Sep 23, 2007 8:11 pm

Sorry - fergot to mention - the 6.6liter PSD soot trap is prolly too large for the 2.8liter CRD - if not properly sized for engine output, the honeycomb will never get hot enuff to burn off the soot, which will then eventually clog the larger unit - don't really take long to clog the correct size in situations where little hiway driving is done, so it would be a big problem with the larger unit, no matter how you drove it

BlackLibertyCRD · **Posted:** Sun Sep 23, 2007 8:15 pm

gmctd wrote:

It would be lots louder, fer sure

Diesel 'cats' are very different from gasser (patooie!) units, which are really catalytic convertors, with platinum element - Diesel units are usually oxidation convertors, or soot traps, where the ceramic honeycomb has no rare earth element, but is merely there to trap the black soot - when you hit the hiway for awhile, the ~625degf exhaust gasses heat the honeycomb, which then burns off the trapped soot, creating relatively harmless ash which exits with the exhaust gasses - do a search on ash, and the human lung

Most states have lenient Diesel inspections today, but that will likely change in '08 because of congress' sudden interest in Green technology, global warming, and all those idiotic Diesel owners that think it's cool to blow billowing black smoke everywhere they go - not only that, but your state is not eligible for federal hiway funding if they don't comply with federal emissions standards, which require state vehicle inspections, controlled from computers at state DOT centers - you drive onto the dyno, the guy (or gal) plugs into the on-board ALDL connector, and a remote robot runs your truck thru it's paces, shuts it off, and a local printer starts reeling off paper indicating parameters passed, parameters failed, and your name logged in DOT databases as a vicious polluter

Oh, yeah - it's comin' - smog cops knockin' on yer doors in the middle of the night, jammin' tracker devices up yer noses, confiscatin' Diesel vehicles and driver licenses - guess who's watchin', even now.......readin'..........takin' notes........makin' lists........................

So the rare occasion I floor it on the highway and blow smoke, that's only ash??...........Double DO'H ........ :roll:

gmctd · **Posted:** Sun Sep 23, 2007 8:28 pm

No, that's unburned soot, if it's dark - maybe even unburned fuel, if your EGT's are up when you see it - you won't see the ash - maybe a very lite gray-to-beige haze, seen in the headlites behind you at nite

brew1 · **Posted:** Sun Sep 23, 2007 9:00 pm

gmctd wrote:

Oh, yeah - it's comin' - smog cops knockin' on yer doors in the middle of the night, jammin' tracker devices up yer noses, confiscatin' Diesel vehicles and driver licenses - guess who's watchin', even now.......readin'..........takin' notes........makin' lists........................

A bit paranoid, aren't we?

Hows that saying go?

I'll give up my soot blowing diesels when they pry them from my dead cold hands.

Catalytic convertor upgrade advise...

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