15 5" exhaust with muffler losing response?

cappa · Oct 28, 2015

I know this had been beat to death but I am trying to decide on either 5" exhaust with a muffler or 4" possibly straight piped. I want it to sound good but don't want super obnoxiously loud either. I have read some posts where guys claim that they lost throttle response with a 5" setup and was just wondering if there is any proof of this or if it's a myth. I would think any free flowing exhaust and a good intake should improve response and spool on a turbo diesel but just wanted to check with the experts. My only other experience with diesels was a 04 6.0 with 4" cool duals mbrp and their muffler and afe stage 2 intake and even on stock tune the response was night and day better than stock. I loved the way that truck sounded with the super raw turbo. I realize I will never get that same screaming turbo sound but just looking for the best setup for my new 15 6.7, thanks

cappa · Oct 28, 2015

I guess I should also mention I am in Canada and plan on a full ******, egr, and ccv. Tuning will prob be sct with gear head tunes unless I hear some good reviews by then about the new ndash

bigrpowr · Oct 28, 2015

there's not really a decibal difference from 4" -5" , its tone. let me know if i can help you out !

20156point7 · Oct 28, 2015

Just go 5 inch strait pipe, it's pretty quite until you get on the throttle then it screams. It's perfect in my opinion

cappa · Oct 28, 2015

Okay thanks. So there is no chance of losing any throttle response with 5" over 4"

SEABEE08FX4 · Oct 28, 2015

cappa said:
Okay thanks. So there is no chance of losing any throttle response with 5" over 4"

No, you could run no exhaust and lose no response. Don't think Gasser when doing Diesel.

dsmracing1 · Oct 28, 2015

Cappa, talk to Jordan at Dirty Diesel Customs. He can give you the hook up on all the good parts from Mike @ No Limit Fabrication and then some. It's well worth the drive to Sylvan Lake. I get all my parts from him....

BR459 · Oct 29, 2015

I agree, I run 5" straight and it's perfect! Great throttle response and sound, actually pretty quiet just cruising, but a good turbo whoosh when you mash it and it screams in the upper RPM's.

BK39 · Oct 29, 2015

Everyone's opinion on loud is different. So it's ultimately it's going to be up to you. I've tried a couple different setups on my 13.
5" straight pipe was loud, and had bad drone.
Added a muffler to it, didn't change anything.
Added a 30" resonator to that, it was too quiet. Pretty much like stock.
Left the resonator in place, removed the muffler, no change.
Removed the entire 5" system, went to a 4" straight pipe. Still loud, but no drone.
If I don't sale the truck within the next couple months, I'll add a muffler just to see what it does.
If I were to start over from scratch, I'd do the 4" pipe with a muffler. Or 5" straight pipe with a 17" resonator.

dsmracing1 · Oct 29, 2015

BK39 said:
Everyone's opinion on loud is different. So it's ultimately it's going to be up to you. I've tried a couple different setups on my 13.
5" straight pipe was loud, and had bad drone.
Added a muffler to it, didn't change anything.
Added a 30" resonator to that, it was too quiet. Pretty much like stock.
Left the resonator in place, removed the muffler, no change.
Removed the entire 5" system, went to a 4" straight pipe. Still loud, but no drone.
If I don't sale the truck within the next couple months, I'll add a muffler just to see what it does.
If I were to start over from scratch, I'd do the 4" pipe with a muffler. Or 5" straight pipe with a 17" resonator.

I think you hit the nail right on the head with that one. I ran a 5" straight pipe and dear baby jesus that was bad when I hooked up to a trailer. I added the muffler and still pretty bad. Added a 17" resonator with the muffler and it was like stock again :badidea: Got rid of the muffler and just kept the 17" resonator with the 5" and BOOM! :toast: It has been like that for over a year now...

cappa · Oct 29, 2015

Yeah I was thinking I was going to try the 5" Flo pro with their muffler and see how it is. Which resonator are you running? Is it the same length as the muffler? You can just remove the muffler section and try a 17" resonator in its place if it is too loud?. I don't mind loud exhaust but back in the day a buddy of mine had a 6l straight piped and I preferred the sound of my mbrp with their muffler to the straight pipe due to the drone at cruising speed.

dsmracing1 · Oct 29, 2015

15 5" exhaust with muffler losing response?

cappa said:
Yeah I was thinking I was going to try the 5" Flo pro with their muffler and see how it is. Which resonator are you running? Is it the same length as the muffler? You can just remove the muffler section and try a 17" resonator in its place if it is too loud?. I don't mind loud exhaust but back in the day a buddy of mine had a 6l straight piped and I preferred the sound of my mbrp with their muffler to the straight pipe due to the drone at cruising speed.

I'm running a twister 17" resonator where the muffler would be yep! I found the 5" with the muffler had a lot of drone for me. You have a 15 though so the characteristics might be slightly different... I don't k own for sure but I'd try with the muffler first for the hell of it.

I'd get a hold of Jordan at Dirty Diesels. He did the engine build on the owner of FloPro's truck with some sweet stuff under the hood...

12 6.7 & 03 6.0 · Oct 30, 2015

I did a 5" inch system on mine and had pretty bad drone. Then tried muffler that came with and no real difference. I took out long (30"?) d-ltete pipe and replaced with a Donaldson muffler. They have dozens of options. You can check flow rate and find something that doesn't restrict your exhaust to badly. It made truck quiet, no drone, towing and hwy but if you get on it all it wakes right up. I took extra step of opening the diverter in the muffler with a long tire bar and I love it. It sounds great now with Streetmax.

BK39 · Oct 30, 2015

cappa said:
Yeah I was thinking I was going to try the 5" Flo pro with their muffler and see how it is. Which resonator are you running? Is it the same length as the muffler? You can just remove the muffler section and try a 17" resonator in its place if it is too loud?

FTE has a 17" or a 30". To eliminate drone everyone suggested putting it as close to the front as possible. But ya, you can probably go that route, just stick it in place of the muffler.