Can I delete or take off my catylatic converter? Do they make a pipe to take its place? Can you buy a high flow cat? Will it improve horsepower, mileage? Will it sound better? Will it make my turbo spool up faster. Basically can it be done and what are the pros and cons. Its a 06 Automatic 3500

 

You can delete it, I think that the DTR store sells a delete pipe.

EGT's will go down a little, MPG will go up .5-1 or so.

I have seen hi pro cat's in the past, but the stock units are good up to 500 hp, I think.

If you tow and have a straight pipe, the drone will make you go nuts at highway speeds.

 

You know honestly the cat really isnt that much of a restriction its the stock muffler thats more of a restriction in the exhaust. I replaced the cat with a test pipe on mine and didnt notice any difference except a bit of sound difference where I noticed the biggest difference was when I took out the stock muffler which you obviously have already done.

As for people talking about the drone on the hwy when towing I havent ever had an issue with drone with 4" straight all the way back while towing heavy or light, however it does get annoying having your passenger side window down when the exhaust reflects off of basically everything and anything thats next to you... I noticed drone with my 96 with 4" straight piped though.

 

The CAT has no effect on HP/TQ.

On my truck (689RWHP) I dynoed with and without...ZERO difference.

 

Good thread for me. I have been searching for this information as I am going to make some changes to my exhaust. Thinking about removing cat and other parts of the exhaust and placing a Donaldson muffler to help with the drone. Since the cat does not hurt performance then I can leave that on and put the new muffler on.

 

Just beware that the EPA law reads if your vehicle has a CAT from the factory you must keep it in the exhaust system. More and more states that have mandatory inspections are starting to enforce this rule. You may be fine but eventually you could get burned, especially the Socialistic Republic of Californication. To each their own.

L8r,...........dogger

 

Keep the cat remove muffler or replace muffler
My plan anyways

 

No change in mpgs, hp/tq.. with minimal change in EGT's.. Biggest change was the time required at idle to cool to 300*.

I mainly deleted mine because of the increased smoke/soot from the Jr; I didn't want to plug it.

 

Not tryin' to jack the thread or anything but I have a question. I went by an exhaust shop to talk about havin' the cat cut and a cutout put in it's place. He said cuttin' the cat out would really wake the truck up. So which is it, the cat or the muffler that's so restrictive?! I want quiet when the wife is in the truck (5% of the time) and loud when it's just me in the truck (95% of the time)

 

The muffler is the restriction...the CAT is a flow thru design and the muffler has bends and chambers in it that kill the noise and hamper flow.

I run a 5" TBE with my CAT made to fit the 5" and I run a Donaldson 51" muffler and it sounds great with minimal interior noise, and its a str8 thru desgn that doesnt hamper flow in any way.

 

I don't know if the later cats work better than my 97 cats but my 97 was plugging up at 19k miles already. It was losing power and the boost and egt were low. Gutting it and welding in a straight piece of pipe thru the shell got all the performance back but not any more than it had before. It looked like a stock cat and I got thru the e-tests no problem on the visual and the tailpipe tests. I would only worry about it if it started running bad. Craig

 

Just make sure you save the cat. Mine was off for 5 years, untill, last week. Needed to get the truck smog checked. The laws changed where I live, I now need to smog the truck. Glad I saved the thing.

 

Removed my cat and had the muffler shop put a straight piece of pipe and installed a nelson muffler i got from the local semi shop.Kept all the old stuff too.

 

Even tho I live in a small town, I too saved all my stuff..... Because you never know

 

I removed my cat, what I noticed is the exhaust fumes are very strong and it was nosier. I reinstalled my cat after 3 weeks, much happier with it. I have a MBRP stainless exhaust from the cat back. it sounds great.