Taking the cat off

[CTD 600]

What would I gain from taking the cat off and replacing the whole exhaust system with a 5" the whole way thru? I seen it done on the TV show Two Guys and a Garage for the TST package. Is taking the cat off only necessary if you are going to BOMB the engine or have some performance upgrades?

 

[JRD]

Performance wise you wont see much of a gain with exhaust like you would in a gasser. The benefit of the exhaust on a diesel is lowering your overall EGT's 100 degrees or so which is a definate plus.

 

[CTD 600]

Is it worth is it? I plan on towing 16k pound trailer. Thanks for the info.

 

[JRD]

In my opinion, every little bit counts. But make sure you choose a nice exhaust system that is free flowing, but yet doesnt "droan" in the cab of the truck while pulling a trailer, which is tough to do with a 5" system from what ive gathered. I personally would go with a nice 4" system minus the cat and stock muffler. Alot of people have been happy with DPPI cat test pipe, (which is a piece of 4" tubing bent and made to replace the cats on the 04. 5 and 05 trucks) and the replacement muffler they offer from MBRP. Another option is to give Rip Rook a call and he'll set you up with exactly what your looking for as well.

Rip Rook can be reached at http://www.protintnw.com/sa_dodgemenu.htm

and Mark at DPPI can be reached at http://www.dieselperformanceparts.com/

whoever you choose will be fine. I havent heard one complaint about these guys in the exhaust department. Good luck.

 

[CTD 600]

Thanks for the info.

 

[Doubleclutch]

Hey Camarillo, hello from up the coast. You've got a 4" exhaust already, how much fuel are you planning on adding? Unless you're planning on adding lots, a 5" system might be overkill. Wait till you get the trailer and gauges before knocking on the 5" exhaust door. Like JRD said, the DRONE is nothing to be taken lightly! As a by-the way, I put a TST box on my 4. 5 and have been having a ball with it. Smokes like my '96 if I'm not careful!

Greg

 

[SHyans]

If your rig is registered in Calif. you may want to look into smog certificate requirements (need cat) and how big a pain ot would be to take on and off for re-certification. They conveniently fail to mention these little details on the TV show as they get you all eager to remove s*** for "better performance".

 

[JCleary]

If your rig is registered in Calif. you may want to look into smog certificate requirements (need cat) and how big a pain ot would be to take on and off for re-certification. They conveniently fail to mention these little details on the TV show as they get you all eager to remove s*** for "better performance".

No smog yet on diesels in CA. If it's allowed to be sold here, there's no testing... But, you can't buy anything but a HD diesel here due to smog restrictions on passenger car diesels.





As far as a 5" exhaust is concerned, I think it's a waste unless you have a big turbo. The stock housing is what, 9cm? Perhaps a bit bigger on the 325/610's? I think *that's* the choke point in the exhaust system.



Not that it wouldn't be cool. I mean, I really want dual 5" stacks, but there's no reason for me to do it..... yet

 

[Matt400]

No smog yet on diesels in CA.

Some fella down south posted about that and said they are doing them. What all is tested/looked at I dunno. I am in an area/zone that only requires a smog on a gasser if you sell it. Nothing at all on Diesels.



If you pull the Cat I would recommend keeping it because they are expensive, over 900. 00 I think. At least you could put it back on.



My CA SO engine sticker and DC smog equipment list shows no Cat.

 

[CStansbury]

Sorry to hijack, but have any of you guys used the DPPI cat test pipe and the Geno's eliminator pipe to straight pipe the whole 4" '04. 5 and later system? If so, did you get any drone from it? I have been thinking about doing that because I like the "log-truck" sound and to remove restrictions for future mods, but I don't want to drive myself mad with drone on the freeway. Thanks.

 

[CStansbury]

I was just looking at Rip's site and noticed the Sneaker muffler. That looks like a nice option instead of the Geno's pipe. Might dampen the drone and still give the straight pipe sound and flow. Anyone got it?

 

[DAWG-1]

Drone

I have a 5" system on my truck from Rip and anything from 2000rpm and has a significant DRONE.



On the positive side it tells me that I an Speeding .



Magnaflow is what I had for a muffler before the change and it sounded fantastic .

 

[tschwab]

Is it worth is it? I plan on towing 16k pound trailer. Thanks for the info.

Tampering or removing emission equipment (CAT CONVERTER) IS A FEDERAL OFFENSE. Sorry, but someone had to say it. Proceed at your own risk. Personally, I don't think you will see any gain by removing it.



What rear axle do you have? If it is a 3. 73 and your towing 16K, your GCVWR is 21K and 23K with 4. 10's I believe, that is what the '05 is. Your truck weighs close to 7K.



If you have 3. 73's your overloaded and if you have 4. 10, your either overloaded or very close to being overloaded. Yeah, the truck will pull it... . BUT it is illeagle and unsafe. If there is an accident and it is determined you were overloaded, you will pay in more ways than one.



Buy the right truck for the job, you need a medium duty truck to safely tow that much weight.

 

[hammersley]

Bingo.............

Tampering or removing emission equipment (CAT CONVERTER) IS A FEDERAL OFFENSE. Sorry, but someone had to say it. Proceed at your own risk. Personally, I don't think you will see any gain by removing it.



Sorry guys but this is a Federal Offense! You will not find any reputable shop that will do this... ... Let's be honest guys - we want to hang all the lawbreakers - except when it involves us of course!

 

[Matt400]

Then don't bomb your trucks cuz the small honey comb chambers are sure to soot up when you start adding more fuel especially if its enough to produce smoke.

 

[Byershome]

"What would I gain from taking the cat off"



Taking it off is illegal, that said, I'd take it off and stow it in your attic or some safe place in case the environmental police come calling. You won't gain much but you will gain something. We are now learning that cats actually create some dangerous emissions themselves.

 

[CStansbury]

So has anyone documented decreased EGT's by the removal of the cat? Or, to those of you with performance mods on your trucks and the stock cat, have you had to remove your cat due to sooting?