4" or 5" Exhaust

[rkadc]

My buddy just traded in his 7.3 PSD for a 07 and he wants to do an exhaust on it, he likes the duals that I have but according to him, to many people have them and he wants to change it up and do a 5" system but is worried that it'll kill his engine. He wants to add a SCT, a nice turbo, some 190cc injectors, to make around 550hp once all is said and done. What would you recommend 4" duals or a 5" single?

[szyd]

4" is all you need

[Abrannan19]

4" will work just fine 5" is just overkill. If you want some prices, let me know, I would be happy to get you some.

[rkadc]

Originally Posted by Abrannan19

4" will work just fine 5" is just overkill. If you want some prices, let me know, I would be happy to get you some.

That'd be cool if you could shoot me some prices for the MBRP 4" aluminum duals and for the 5" installer series


If he did use a 5" would he basically be killiing his truck until he added the inejctors and turbo? I know back when I had my 97 cummins, when I did my stack I changed from 4" to 5" and it really didn't feel like I lost anything but that truck was pushing alot more fuel than what my friend is trying to get out of his 6.0

[dieselmast]

You don't need backpressure on a diesel! Everybody keeps thinking they will lose power with a bigger exhaust. You won't! You gain power with a bigger exhaust. These are not the same as gas motors, guys.

[PGreenSVT]

Originally Posted by dieselmast

You don't need backpressure on a diesel! Everybody keeps thinking they will lose power with a bigger exhaust. You won't! You gain power with a bigger exhaust. These are not the same as gas motors, guys.

Yeah, turbos don't like to see back pressure. You'll only gain a little deeper tone with the 5" though. 4" is plenty big enough.

[Makolab]

Heck, just last week I went to the muffler shop and the guys there cut out the muffler and the cat so now Im runnin a straight pipe with the 3 1/2" stock pipe. It sounds GREAT, runns really well and I kept the 3 1/2 cus the guy said that no matter what size you put behind the engine, your down pipe is still 3". He didnt recommend the larger pipes unless you got a larger down pipe. What do y'all think??

[smokersteve]

4" will be good

[DSTRBD]

4" is all you really need but 5" does look and sound great. Check out the promotions we have going right now, MBRP gets my vote for the best 6.0L kit. Feel free to give me a holler with any questions you may have.

[Raul@Stealth Automotive]

i would stick to a 4" straight pipe unless he wanted that lil bit lower droan