Another exhaust Q for smog

[cww909]

So yes I'm a newb, but have been doing some searches for an exhaust that I can run in a Smog county in Nevada (Washoe Co.). Just curious if there is an exhaust that is turbo back with the cat and no muffler? I'm new to the forum and also the diesel world (as a new owner, family has always had one.)

I'm not looking to spend a ton, but if need be then I will. Just don't want to be taking on and off a cat every year at inspection/smog, unless it's relatively easy. Also, not sure about getting stopped by the popo without a cat? Fine involved possibly? I see modded up diesels running around town blowin smoke and sounding mean so I'm sure there are ways around the smog issue.



Well, any help is much appreciated!

-Curtis

[windrunner408]

So your looking for a turbo back with CAT straight pipe? If that is indeed the case I have never heard of such a thing. Maybe a CAT back straight pipe, but every turbo back exhaust (whether with or without a muffler) I have heard of does not include a cat but rather a means to keep your existing cat. Kind of a waste if you ask me because if you have a 4in down pipe then constrict the piping back to 3.5 in then open it back up after the cat to 4in you are defeating the purpose of the 4in exhaust IMO. However, I do know that xtremediesel use to sell replacement CATs in 3.5, 4, and 5in diameters. I dont remember how much they were but if you have to keep the cat then this is what I would do. I would go with the 4in or 5in turbo back exhaust and just get a CAT for that diameter piping. I know it would be more but if you are ok with that then great. Hope this helps.

[cww909]

Originally Posted by windrunner408

So your looking for a turbo back with CAT straight pipe? If that is indeed the case I have never heard of such a thing. Maybe a CAT back straight pipe, but every turbo back exhaust (whether with or without a muffler) I have heard of does not include a cat but rather a means to keep your existing cat. Kind of a waste if you ask me because if you have a 4in down pipe then constrict the piping back to 3.5 in then open it back up after the cat to 4in you are defeating the purpose of the 4in exhaust IMO. However, I do know that xtremediesel use to sell replacement CATs in 3.5, 4, and 5in diameters. I dont remember how much they were but if you have to keep the cat then this is what I would do. I would go with the 4in or 5in turbo back exhaust and just get a CAT for that diameter piping. I know it would be more but if you are ok with that then great. Hope this helps.

Thanks for shedding some light for me I'm not super mechanical, but smart enought to understand if things are explained. I wasn't sure if there were any companies that made an exhaust that included an oversized CAT or not. I've done some searches, but am not super familiar and not all of the companies list diameters (well through the wholesalers).

I agree with what you recommend, and will be going with either a 4 or 5in turbo back. I believe one of the companies makes a "tester" tube that is a section of straight tube that replaces the CAT and can put the CAT back in for smog purposes. Thats probably the system that I'll go with (MBRP I believe). I'm not planning on big mods (everyone says that right lol), just exhaust and a tuner (SCT plus Edge Insite).

-Curtis

[windrunner408]

Got ya. Yea the ideal system would be one that you can easily swap the CAT in and out of without changing the diameter of the pipe when it is out.

Great idea for the Edge Insight. I recommend those to anyone who will listen. Single best mod you can do to your truck since it allows you to see how each mod you do affects your motor.