Worth it to remove Cat in 2006?

[JCockerill]

I was installing my banks exhaust today, and was wondering how much of a restriction the car is. Banks told be it was a through cat, but i looked in and it is all honeycolm in there. looks like a big restriction. Is it worth it to strait pipe the cat before i install the exhaust? I'm not happy banks didn't tell me the right thing. i really wanted a turbo back exhaust, but they said there was no need because of the 4 in downpipe and the "through" cat. thanks for the help.

 

[TAbbott]

My understanding is the Cat actually has very little restriction.....

 

[BHaden]

My understanding is the Cat actually has very little restriction.....

I hooked up an old Autometer 30psi boost gauge to a brass nipple in front of the cat on my 06 and even under heavy throttle only saw about 2 psi. I would not be surprised if that went up noticably if you have modded the engine much. Mine has a Roktek muffler so that may skew results a little, but I doubt much.

 

[JCockerill]

so i should just leave it alone then?

 

[Ducman82]

taking it off is against the law in every state... . that being said i lost mine when turbo back 5 inch got installed, not sure where it went, might have rolled under work bench. but it flows better... ... . seams like it any who. def lower egts?

 

[AH64ID]

From what I have read its only about a 2-4 rwhp loss with it on...

On a fairly close to stock fueled truck I wouldn't worry about, if you have a heavily fueled truck, or one that smokes a lot I may think about "testing" the exhaust without it...

 

[Ducman82]

i do notice a BIG diffrence in smoke, lots more.

 

[JCockerill]

i just got the banks six gun bundle. exhaust, intake, and six gun tuner. should i loose it or what?

 

[Ducman82]

just depends on the amount of work you want to do.

 

[XtremeDiesel]

it's true it depends how lound and how much work you wanna do. really the only real benefit is a little lower egts and maybe another 1-2mpg increase.

 

[JCockerill]

it's true it depends how lound and how much work you wanna do. really the only real benefit is a little lower egts and maybe another 1-2mpg increase.

i want whatever is better for the truck. if it will save me mpg's then i'm in... and lower egt's is good too right? will it cause any turbo lag, or loss of boost by removing it? thanks

 

[mrtrombley]

Hi, new here and found this thread. I have an '04. 5/600 and am contemplating a 4" straight exhaust, removing the catalytic and muffler altogether. Will this hurt any settings? Will it be TOO loud? The truck has 93K plus on it right now. I know by law you are not supposed to do this, but has anyone ever been stopped? I do pull RV's for for a Transport Co. once in a while and have to go through weigh stations, will they stop me for a straight pipe exhaust.



I have a Bully Dog unit which makes the truck run great, but I have always been looking for a little better fuel mileage. Would a large air intake system and the straight pipe help or hurt mileage?



Any advice would be appreciated. The truck has 93K plus on it right now. It is a 4wd (reason enough for poor mileage).



Thanks

 

[XtremeDiesel]

no it won't cause any issues. infact you might spool up a bit better w/ both of you guys having programmers.



i would say that any air mod would help your fuel mileage.



also i would highly suggest an upgraded fuel system like the Airdog kit, i've seen 1-2 mpg increase on a stock truck w/ that kit.

 

[jmccart]

There was an article in Diesel Power magazine. They did a dyno & EGT before & after comparo. HP was hardly different at all. EGT's were quite lower w/o the cat.

 

[WKruger]

Buddy seen a 150 deg. drop when he removed his. W/ that noticed a slight improvement in performance. Fuel mileage, about the same.

 

[Ducman82]

Granted i did 5" turbo back, but i got way lower EGT's, quicker spooling, but i have yet to see any MPG increase.

 

[AH64ID]

I have yet to hear of any real mpg gain on these rigs from loosing the muffler/cat. . . Mine didn't make a mpg difference, but it made an EGT difference, not much but it was there...

I have no muffler but left the cat, and when towing above 2K rpms it gets loud quick... I am contemplating going to a Aero 4040XL, and possibly testing the truck w/out the cat... .

 

[PAngelos]

I put a trubo back exhaust from J. Jardine on my truck and the drone in the truck was LOUD when you towed anything. I ended up putting mine back on and am much happier with the cat on. I did notice a little power loss when i reinstalled the cat but the smarty MORE than makes up for it and the noise in the cab is way eaiser on the ears

 

[mrtrombley]

"also i would highly suggest an upgraded fuel system like the Airdog kit"



Ok, I have to ask. What is the Airdog?

 

[mrtrombley]

Its interesting that you mentioned Jardine, because that is where I will go if I do the exhaust. They did my last truck from the cat back. I pretty much trust what they say and their prices are real good. Quoted around $400 for a 4" turbo back, installed. I really like to use the exhaust as a reason to take a mini vacation to WY. Beautiful country up there. Last time I took the bike with me and rode to Jackson Hole and around Yellowstone for the weekend and then left Monday after they put the pipes on.