straight pipe exhaust question
 

Hey guys I have a few questions about putting an exhaust on my truck my smog is up next mo. So im gonna do it after that but i wanna get all my ducks in a row before I do so.

First question: which straight pipe is preferred and does size matter

Second question: this one could potentially get me shot but I didnt notice an O2 sensor but if it does have one that i just didnt notice how would you go about not thowing a code for emmisions? If it doesnt have one then this question doesnt apply

Being as its gonna be a straight pipe does the brand really matter as long as its manderal bent and when i ask if size matters i mean 4" vs 5" turbo back

Thanks guys

The 6.0L doesn't have O2 sensors. You don't even need to have a brand name, my local shop bent my 4" for me, I bought a 4" downpipe and they bent the rest. As far as 4" or 5", that depends on what your plans are, 4" is fine for stock trim-slight mods, you start getting into serious mods and you'll need the extra flow of a 5". Same goes for where it exits, stacks/under the cab/in front of the tire/behind the tire, that is all personal preference.

1) Buy what ever brand/material you can afford. Size doesn't matter since it will be unrestricted flow.

2) Does not apply.

Have fun...make sure you start working the late shift or early shift. Your neighbors will love to hear you leaving for work.

Size wont matter. 5" will probably have a slightly deeper tone, the 4" will be a touch raspier.

There are 1000hp trucks running 4" exhausts, you'll be fine.

Check clearences when bolting it up. I thought I had enough on my cross member once, the rattle was ANNOYING. Regardless of what you buy, get a turbo back and ditch the 3" down pipe. I am plenty happy with 3.5 DP/4" straight pipe.

It's going to scream when you ditch the cat/resonator! :w2: While most will like it, there will always be the hater asking why you did that. :bat: Also be prepared for "What kind of turbo is that?" Most people don't believe an OEM turbo can scream like that and it has to be an aftermarket turbo.

Never even thought about him having the 03 turbo... I'm jealous. Ear piercing whistle! :c:

I live in ca so when smog comes around I'm gonna need a cat is there a kit that has a bolt on straight pipe but then I can easily install my stock cat when the time comes around?

@dieseldaddy: how much did that run you

Yeah most of them you can do that. You can also just get a muffler delete and a cat delete pipe, they're not really expensive. Everything on the stock system can bolt/unbolt. The only thing you'd have to destroy to put a different exhaust on is the down pipe needs to be cut.

Considering you just did a hpop swap, switching from cool guy straight pipe to el lameo cat exhaust would be a walk in the park. If you can support the trans, it LOOKS like the down tube would fall right out without the cross member in place. At least that's what I iwas thinking when I was wanting the down tubeout of the way for my EGR cooler delete job.

One option you have is a 3.5" downpipe which has the flange to bolt the cat on when it comes time for inspection (about $150-200 depending who you get it from). The other option you have is to do what my buddy Martin and I did with 03-07 Ford 6.0L Powerstroke Diesel 4" Aluminized Turbo Downpipe 125050 (because like an idiot I put my straight pipe on before CA started doing inspections and scrapped the stock shit), he cut his cat down and welded 2 3-bolt flanges on, then cut the same length out of his straight pipe and welded flanges there too, I also did the same, so when it comes time for one of us to smog, it's as simple as 6 bolts out, drop the section, raise the cat, 6 bolts in, 5 minutes tops. Which reminds me, I need to get my hands on a cat since he is going back up north this year.