Size of stock cat

Anything related to the factory RPO Crew Cab.

Moderator: F9K9

paintballrocker
Crew Elite
Crew Elite
Posts: 356
Joined: Sun Mar 01, 2009 10:15 pm
Location: RAF Lakenheath, UK
Contact:

Size of stock cat

Post by paintballrocker »

My stock cat is bad; rattling, loss of power, shitty gas mileage. anyways im going to order a hi flow cat and just need to know what size inlet/outlet i need so it fit the factory exhaust. im considering the magnaflow spun cat, would that be a good choice?

thanks


also when i take it to the exhaust shop i was thinking of having them delete the pre cat and replace it with exhaust pipe, would that be a good idea? i dont want to set off a code, but if it can be deleted id like to do it
[size=75]2002 CC, westin push bar with 2 lights, bed cover, custom made cat-back exhaust.......soon a steering stabilizer mod, lift, sounds system[/size]
User avatar
F9K9
Mod K Elite
Mod K Elite
Posts: 6183
Joined: Sun May 30, 2004 12:26 pm
Location: London, Kentucky, United States

Re: Size of stock cat

Post by F9K9 »

What's your mileage? Under 80K let dealer fix it.
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
[url=http://www.naxja.org/forum/showthread.php?t=73349]GUIDE TO SEARCHING. [i] (Some of the forum software is different but, it has helped me a lot.)[/i][/url][/b]
[b]"Those who don't know history are destined to repeat it." Edmund Burke[/b][/size]
paintballrocker
Crew Elite
Crew Elite
Posts: 356
Joined: Sun Mar 01, 2009 10:15 pm
Location: RAF Lakenheath, UK
Contact:

Re: Size of stock cat

Post by paintballrocker »

i wish mine had 80,000 haha. mine sadly has 147,XXX
[size=75]2002 CC, westin push bar with 2 lights, bed cover, custom made cat-back exhaust.......soon a steering stabilizer mod, lift, sounds system[/size]
User avatar
F9K9
Mod K Elite
Mod K Elite
Posts: 6183
Joined: Sun May 30, 2004 12:26 pm
Location: London, Kentucky, United States

Re: Size of stock cat

Post by F9K9 »

Well, since Brule and I are running 3" cat back exhausts, I believe the the cats are 3" in and 3" out" :mrgreen:
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
[url=http://www.naxja.org/forum/showthread.php?t=73349]GUIDE TO SEARCHING. [i] (Some of the forum software is different but, it has helped me a lot.)[/i][/url][/b]
[b]"Those who don't know history are destined to repeat it." Edmund Burke[/b][/size]
User avatar
HenryJ
Admin K Elite
Admin K Elite
Posts: 12705
Joined: Tue Oct 01, 2002 9:14 pm
Location: Ontario, Oregon
Contact:

Re: Size of stock cat

Post by HenryJ »

Yup! 3" in/out high flow. The pipe is necked down to 2 1/2" fore and aft.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK
paintballrocker
Crew Elite
Crew Elite
Posts: 356
Joined: Sun Mar 01, 2009 10:15 pm
Location: RAF Lakenheath, UK
Contact:

Re: Size of stock cat

Post by paintballrocker »

ok so the stock size of the inlet/outlet of the cat is 3"?
[size=75]2002 CC, westin push bar with 2 lights, bed cover, custom made cat-back exhaust.......soon a steering stabilizer mod, lift, sounds system[/size]
User avatar
F9K9
Mod K Elite
Mod K Elite
Posts: 6183
Joined: Sun May 30, 2004 12:26 pm
Location: London, Kentucky, United States

Re: Size of stock cat

Post by F9K9 »

HenryJ wrote:Yup! 3" in/out high flow.....................
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
[url=http://www.naxja.org/forum/showthread.php?t=73349]GUIDE TO SEARCHING. [i] (Some of the forum software is different but, it has helped me a lot.)[/i][/url][/b]
[b]"Those who don't know history are destined to repeat it." Edmund Burke[/b][/size]
paintballrocker
Crew Elite
Crew Elite
Posts: 356
Joined: Sun Mar 01, 2009 10:15 pm
Location: RAF Lakenheath, UK
Contact:

Re: Size of stock cat

Post by paintballrocker »

wow i cant believe i missed that. lol thanks
[size=75]2002 CC, westin push bar with 2 lights, bed cover, custom made cat-back exhaust.......soon a steering stabilizer mod, lift, sounds system[/size]
User avatar
F9K9
Mod K Elite
Mod K Elite
Posts: 6183
Joined: Sun May 30, 2004 12:26 pm
Location: London, Kentucky, United States

Re: Size of stock cat

Post by F9K9 »

paintballrocker wrote:wow i cant believe i missed that. lol thanks
Don't feel bad, I do it all the time! :mrgreen:
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
[url=http://www.naxja.org/forum/showthread.php?t=73349]GUIDE TO SEARCHING. [i] (Some of the forum software is different but, it has helped me a lot.)[/i][/url][/b]
[b]"Those who don't know history are destined to repeat it." Edmund Burke[/b][/size]
User avatar
rlrnr53
Crew Elite
Crew Elite
Posts: 557
Joined: Wed Dec 28, 2005 2:04 pm
Location: Prosperty, West Virginia

Re: Size of stock cat

Post by rlrnr53 »

CRS syndrome?
[size=75]Mitch
2001 Polo Green Metallic, no mods,(can't afford any)[/size]
paintballrocker
Crew Elite
Crew Elite
Posts: 356
Joined: Sun Mar 01, 2009 10:15 pm
Location: RAF Lakenheath, UK
Contact:

Re: Size of stock cat

Post by paintballrocker »

well my new cat came in thursday. im pretty impressed with JEGS, i ordered it tuesday and it was at my door after work on thursday. the shop is gona get me in friday the 18th. do you think it would be a good idea to have the pre cat deleted?
[size=75]2002 CC, westin push bar with 2 lights, bed cover, custom made cat-back exhaust.......soon a steering stabilizer mod, lift, sounds system[/size]
User avatar
F9K9
Mod K Elite
Mod K Elite
Posts: 6183
Joined: Sun May 30, 2004 12:26 pm
Location: London, Kentucky, United States

Re: Size of stock cat

Post by F9K9 »

Wouldn't hurt.
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
[url=http://www.naxja.org/forum/showthread.php?t=73349]GUIDE TO SEARCHING. [i] (Some of the forum software is different but, it has helped me a lot.)[/i][/url][/b]
[b]"Those who don't know history are destined to repeat it." Edmund Burke[/b][/size]
Jongo88
Crew Elite
Crew Elite
Posts: 374
Joined: Sun Jan 25, 2009 6:33 pm
Location: Valrico, Fl.

Re: Size of stock cat

Post by Jongo88 »

I would... And I did....
2002 GMC Sonoma crew cab 4x4. Tb mod, Air box mod, pre cat delete,B&M shift improver, Trans cooler, Big three ,AD-244 alt,Red top Optima, e-fan, HD Radaitor,265/70-16' on 16x8 TA wheels,, t-bar tweek, 1.5 inch shackles and 2 inch body lift,Skids fender trim, 1.5 inch wheel spacers in front and 2.5 in back, Quad mod and Frog lights.
Transfercase vacuum switch change DO IT!!!
paintballrocker
Crew Elite
Crew Elite
Posts: 356
Joined: Sun Mar 01, 2009 10:15 pm
Location: RAF Lakenheath, UK
Contact:

Re: Size of stock cat

Post by paintballrocker »

does the pre cat affect emissions? because the guy said he isnt sure if he could legally delete it if it does because of the emisions laws in PA. but he said he'll look at it friday and see if it can be deleted
[size=75]2002 CC, westin push bar with 2 lights, bed cover, custom made cat-back exhaust.......soon a steering stabilizer mod, lift, sounds system[/size]
User avatar
killian96ss
Crew K Elite
Crew K Elite
Posts: 2669
Joined: Tue Sep 09, 2003 11:53 am
Location: Sacramento, California

Re: Size of stock cat

Post by killian96ss »

It is illegal to remove ANY part of the emission system including the pre-cat. A lot of the automotive forums out there do not condone or allow members to talk about removing emission equipment because it is a violation of federal law. Most shops will not remove a cat because of the liability, but there are still plenty that will do it. The pre-cat is not needed to pass tailpipe emission testing. It is really only there to reduce start up emissions while the engine is cold. It also helps prolong the life of the main cat by heating it up faster.

Steve
User avatar
F9K9
Mod K Elite
Mod K Elite
Posts: 6183
Joined: Sun May 30, 2004 12:26 pm
Location: London, Kentucky, United States

Re: Size of stock cat

Post by F9K9 »

Steve lives on the left coast and you live in PA. Each state has their own laws and inspection regulations that are in addition to the fed rules. Research PA inspection rules to be sure. Or we can discuss the current AZ reg that echoes the fed law and is so "in" to whine about.
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
[url=http://www.naxja.org/forum/showthread.php?t=73349]GUIDE TO SEARCHING. [i] (Some of the forum software is different but, it has helped me a lot.)[/i][/url][/b]
[b]"Those who don't know history are destined to repeat it." Edmund Burke[/b][/size]
fallvitals
Crew K Elite
Crew K Elite
Posts: 1132
Joined: Tue Mar 03, 2009 2:34 am
Location: Dunbar, WV
Contact:

Re: Size of stock cat

Post by fallvitals »

F9K9 wrote:Steve lives on the left coast...
I got a chuckle from that.
User avatar
border man
Crew Elite
Crew Elite
Posts: 475
Joined: Sat Nov 15, 2003 12:06 pm
Location: AZ
Contact:

Re: Size of stock cat

Post by border man »

F9K9 wrote:Steve lives on the left coast and you live in PA. Each state has their own laws and inspection regulations that are in addition to the fed rules. Research PA inspection rules to be sure. Or we can discuss the current AZ reg that echoes the fed law and is so "in" to whine about.

You ain't going to hear me whine about it :roll:
[size=75]I didn't do it, it was already like that when I got it.[/size]
User avatar
F9K9
Mod K Elite
Mod K Elite
Posts: 6183
Joined: Sun May 30, 2004 12:26 pm
Location: London, Kentucky, United States

Re: Size of stock cat

Post by F9K9 »

border man wrote:
F9K9 wrote:...............Or we can discuss the current AZ reg that echoes the fed law and is so "in" to whine about.

You ain't going to hear me whine about it :roll:
:roflmao: :roflmao:
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
[url=http://www.naxja.org/forum/showthread.php?t=73349]GUIDE TO SEARCHING. [i] (Some of the forum software is different but, it has helped me a lot.)[/i][/url][/b]
[b]"Those who don't know history are destined to repeat it." Edmund Burke[/b][/size]
paintballrocker
Crew Elite
Crew Elite
Posts: 356
Joined: Sun Mar 01, 2009 10:15 pm
Location: RAF Lakenheath, UK
Contact:

Re: Size of stock cat

Post by paintballrocker »

well i got the new cat put in today, no more rattling lol. but i have a odd Q now. since the new cat was put in i put 30mi on it so far and ive noticed my exhaust tone has gotten alot quiter and higher pitched, it used to be a nice deep tone but now can harrdly be heard. any thought as to why it did this?
[size=75]2002 CC, westin push bar with 2 lights, bed cover, custom made cat-back exhaust.......soon a steering stabilizer mod, lift, sounds system[/size]
User avatar
F9K9
Mod K Elite
Mod K Elite
Posts: 6183
Joined: Sun May 30, 2004 12:26 pm
Location: London, Kentucky, United States

Re: Size of stock cat

Post by F9K9 »

paintballrocker wrote:...........................any thought as to why it did this?
Not a clue. :crazy:
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
[url=http://www.naxja.org/forum/showthread.php?t=73349]GUIDE TO SEARCHING. [i] (Some of the forum software is different but, it has helped me a lot.)[/i][/url][/b]
[b]"Those who don't know history are destined to repeat it." Edmund Burke[/b][/size]
paintballrocker
Crew Elite
Crew Elite
Posts: 356
Joined: Sun Mar 01, 2009 10:15 pm
Location: RAF Lakenheath, UK
Contact:

Re: Size of stock cat

Post by paintballrocker »

me either. im stumped
[size=75]2002 CC, westin push bar with 2 lights, bed cover, custom made cat-back exhaust.......soon a steering stabilizer mod, lift, sounds system[/size]
User avatar
killian96ss
Crew K Elite
Crew K Elite
Posts: 2669
Joined: Tue Sep 09, 2003 11:53 am
Location: Sacramento, California

Re: Size of stock cat

Post by killian96ss »

Did you have the pre-cat deleted? Is the new main cat bigger than the stock cat?

Steve
User avatar
roadrunner
Crew K Elite
Crew K Elite
Posts: 1267
Joined: Wed Dec 05, 2007 5:39 pm
Location: NW KS

Re: Size of stock cat

Post by roadrunner »

I'd venture a guess that since your old cat was rattling it may have suffered internal damage causing possible bypass of exhaust internally which would cause it to have a deeper tone. Kinda like having the difference between a partly empty can (old cat) in the system versus a fully deadened (new cat) new part. Us old timers used to gut out glass-pack mufflers causing them to go deep and loud in the same manner. Empty chamber in the exhaust line=less back-pressure and also a larger sound chamber giving that echo-deep note.
2001 CC LS, pewter, stock, 4.3,Wait4meperformance, CFM throttle blade, Helix throttle body spacer, 4spd auto, 3button electric 4x4 shift, heavy duty factory suspension, Bilsteins, 1" rear wheel spacers, skid plates.
paintballrocker
Crew Elite
Crew Elite
Posts: 356
Joined: Sun Mar 01, 2009 10:15 pm
Location: RAF Lakenheath, UK
Contact:

Re: Size of stock cat

Post by paintballrocker »

Did you have the pre-cat deleted?
nope cause of emissions testing
Is the new main cat bigger than the stock cat?
not sure, i know the new cat is smaller in length. its 3' in/out with a 4" body where the honey comb stuff is located
Kinda like having the difference between a partly empty can (old cat) in the system versus a fully deadened (new cat) new part
thats what i was thinking, but i liked the deeper tone :cry:
[size=75]2002 CC, westin push bar with 2 lights, bed cover, custom made cat-back exhaust.......soon a steering stabilizer mod, lift, sounds system[/size]
User avatar
dozer1530
Crew Elite
Crew Elite
Posts: 152
Joined: Tue Jun 22, 2010 4:53 am
Location: houston / sugarland tx
Contact:

Re: Size of stock cat

Post by dozer1530 »

dose anny one know how much it would cost to get a new pre cat and new main cat from dealer cuz i only have 81000 miles on my cc and i think mine are clogged
User avatar
HenryJ
Admin K Elite
Admin K Elite
Posts: 12705
Joined: Tue Oct 01, 2002 9:14 pm
Location: Ontario, Oregon
Contact:

Re: Size of stock cat

Post by HenryJ »

The precat is known to be a "problem child". Personally, I'd just eliminate the precat if at all possible. Yea, yea, I know "...illegal to tamper with emissions components." The main cat will still pass the sniffer tests and be as clean as it was originally.
If you are required to pass a visual inspection, then ditch'n the precat may not be an option.

I do not know what the precat, cat and piping might cost from the dealer. If I had to guess and if it is available, I bet it is close to $2000 or more. I know that a late model full size runs about that much.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK
User avatar
dozer1530
Crew Elite
Crew Elite
Posts: 152
Joined: Tue Jun 22, 2010 4:53 am
Location: houston / sugarland tx
Contact:

Re: Size of stock cat

Post by dozer1530 »

but i think i have a sensor going into my pre cat? i just looked and i didnt see one im gona see if i can find a shop that will cut it off and add a new pipe in its place
User avatar
HenryJ
Admin K Elite
Admin K Elite
Posts: 12705
Joined: Tue Oct 01, 2002 9:14 pm
Location: Ontario, Oregon
Contact:

Re: Size of stock cat

Post by HenryJ »

Two before and one after the main. No sensors in the cats.

A shop can not remove the cat. Legally they can only replace it. In the case of the precat they can provide a pipe to replace that section if it is missing. They don't have to know a precat was there.
You may find a sympathetic shop who can help you, but don't count on it. They may not wish to risk the consequences.
Having it tested and then contacting GM customer service for a good faith replacement might be another option? Dodge warranted their emission parts for 12 years unlimited mileage on some models.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK
User avatar
dozer1530
Crew Elite
Crew Elite
Posts: 152
Joined: Tue Jun 22, 2010 4:53 am
Location: houston / sugarland tx
Contact:

Re: Size of stock cat

Post by dozer1530 »

so if i can find some one to cut it out and add a pip were it was it wont give me a dash light?
User avatar
HenryJ
Admin K Elite
Admin K Elite
Posts: 12705
Joined: Tue Oct 01, 2002 9:14 pm
Location: Ontario, Oregon
Contact:

Re: Size of stock cat

Post by HenryJ »

dozer1530 wrote:so if i can find some one to cut it out and add a pip were it was it wont give me a dash light?
Pre-cat Delete???

Plugged Pre-cat

No problems in six years here.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK
User avatar
border man
Crew Elite
Crew Elite
Posts: 475
Joined: Sat Nov 15, 2003 12:06 pm
Location: AZ
Contact:

Re: Size of stock cat

Post by border man »

Time for a sawzall. Dozer to muffler shop "My exhaust pipe rusted through right about here.... can you replace the bad section I cut out....." :roll:
[size=75]I didn't do it, it was already like that when I got it.[/size]
User avatar
dozer1530
Crew Elite
Crew Elite
Posts: 152
Joined: Tue Jun 22, 2010 4:53 am
Location: houston / sugarland tx
Contact:

Re: Size of stock cat

Post by dozer1530 »

:roflmao: i wish that would work i went two 3 places already and they keep telling me no if anny one is in the houston or sugar land tx area and knows a place that will do it plzz let me know
User avatar
HenryJ
Admin K Elite
Admin K Elite
Posts: 12705
Joined: Tue Oct 01, 2002 9:14 pm
Location: Ontario, Oregon
Contact:

Re: Size of stock cat

Post by HenryJ »

Do it yourself. Sawzall, pipe, and two band clamps.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK
User avatar
dozer1530
Crew Elite
Crew Elite
Posts: 152
Joined: Tue Jun 22, 2010 4:53 am
Location: houston / sugarland tx
Contact:

Re: Size of stock cat

Post by dozer1530 »

what you mean. oo ok so i cut it off and then get a pice of pipe that fits and the clamp it on ?
User avatar
HenryJ
Admin K Elite
Admin K Elite
Posts: 12705
Joined: Tue Oct 01, 2002 9:14 pm
Location: Ontario, Oregon
Contact:

Re: Size of stock cat

Post by HenryJ »

Yes. Use stainless steel band clamps. That will work until you find a place to weld it up.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK
User avatar
dozer1530
Crew Elite
Crew Elite
Posts: 152
Joined: Tue Jun 22, 2010 4:53 am
Location: houston / sugarland tx
Contact:

Re: Size of stock cat

Post by dozer1530 »

ok i just got back from dealership cuz i had that recall on the tail gate cables they didnt have any :(. but i had my cats chekt out and they are fine it was a program issue they redid it and its ruining great now. im gona fill up next week and chek the millage
User avatar
HenryJ
Admin K Elite
Admin K Elite
Posts: 12705
Joined: Tue Oct 01, 2002 9:14 pm
Location: Ontario, Oregon
Contact:

Re: Size of stock cat

Post by HenryJ »

Sounds a little fishy to me.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK
User avatar
dozer1530
Crew Elite
Crew Elite
Posts: 152
Joined: Tue Jun 22, 2010 4:53 am
Location: houston / sugarland tx
Contact:

Re: Size of stock cat

Post by dozer1530 »

i had a tuner on it and then reloaded my stock and i kep getting an err so i unplugged the battery. then i tried angian and it worked. but when i took it to the dealership it showed i had some errs so cuz im still under warranty he redid it and he said if i want i can come back to marrow and get a new pre cat put on. i trust them cuz the mechanic is my brother in law.and i use hi, every time i have a warranty issue and he all ways gets it done. what he did was put a hole on each side of the pre cat like my dad had told me to do and see if the presher was the same and we did this to the main cat as well
so tomorrow ill just have a new one put on any way. hes just gona warranty it out and when i find a shop ill get it cut out. i ask if he could but hes not the welder there lol
Last edited by dozer1530 on Thu Aug 05, 2010 9:12 am, edited 1 time in total.
User avatar
HenryJ
Admin K Elite
Admin K Elite
Posts: 12705
Joined: Tue Oct 01, 2002 9:14 pm
Location: Ontario, Oregon
Contact:

Re: Size of stock cat

Post by HenryJ »

Ok, the details make more sense.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK