Horsepower & 5 inch exhaust

[CLAYTON]

Howmuch horsepower would you need to take advantage of a 5 inch exhaust? I want to put some DDIII's on truck. Of course gauges are next and then a Afe intake... (should be here in a couple of days) So with the Edge Ez lvl 6, DDIII's and Afe intake what would be better. . a 4 or 5 inch exhaust?

 

[BillGotthelf]

5" exhaust's are for 500+ HP. Usually that means twins unless you are Joe D. Get a good 4" its all you need.

 

[KLockliear]

4" and 5" make no HP differences or EGT differences on the 03/04... just sound. They both have the same EGT differences from the stock system.

 

[Matt S]

Is the sound deeper with the 5"? Or is the drone louder?

 

[Joseph Donnelly]

I estimate it takes 570 hp at the wheels to see any benefit, however slight, from 5" and you can make over 600 with 4". These numbers are with a single turbo and #2 diesel fuel only. Noise and drone are noticeably higher with 5". I have 5" on Sickly and put 4" on my 2004. Hope this helps.

 

[CLAYTON]

Originally posted by Joseph Donnelly

I estimate it takes 570 hp at the wheels to see any benefit, however slight, from 5" and you can make over 600 with 4". These numbers are with a single turbo and #2 diesel fuel only. Noise and drone are noticeably higher with 5". I have 5" on Sickly and put 4" on my 2004. Hope this helps.

I think that I will go with a 4" system... hummm now the hard part of picking one

 

[XcumminsX]

mbrp or whatever there called from bigexhaust.com i love mine and it was cheap. 429 at the time... And yes its ss and mirror polished



Nick

 

[CLAYTON]

Originally posted by XcumminsX

mbrp or whatever there called from bigexhaust.com i love mine and it was cheap. 429 at the time... And yes its ss and mirror polished



Nick

Does yours have any drone to it... and does it come with the 4" down pipe? How do you like the sound in normal driving and freeway speeds?

 

[XcumminsX]

there is a drone but i like it... Not annoying at all... Yes its a 4" downpipe all the way threw... 1 thing though i believe they raised the price to 499. . And it sounds awesome on the streets/ highway

 

[DocDetonancour]

? for Joe D?

Joe, do you know if there is any h. p, torque, or mpg gain with a "better" 4" system? Thanks, Doc

 

[HDerrick]

Ordered 5 inch BD exhaust systems

I am having the the new just released 5 inch BD Power exhaust system installed tomorrow. I should have the details tomorrow night.

 

[CLAYTON]

Does anybody out there make a SS 5"? I bet that wouldn't be cheap

 

[Joseph Donnelly]

Look for several things in a system: aluminized steel (or stainless if your wallet is thick); straight through muffler with perforated core, no louvers in the flow path; good hangers, good fit. Be sure it has mandrel bends for good flow.

 

[Mark Craig]

5 inchers

Clayton,



The truck will for most folks experience a loss of low end torque in 0-40 MPH stop light to stop light situations with a 5 inch system unless you are at or over 500 RWHP. Been there and done that and seen it happen, that's why for the vast majority of folks a 4 inch system is the best egt reduction HP improvement available. Picking aluminized or 409/304 stainless is you're next hurdle to decide on. The factory 2003/-4 system is a much better material than the 24 valve system was and is a low grade stainless steel. You might want to consider duals for a really neat rear "view" appearance etc. We will be glad to answer any questions you might have.



Mark @ DPPI

 

[Davey]

What if the five inch system starts @ 4" and expands to 5" after a few feet?

 

[lmills]

most 5 " kits start with a 4" down pipe

 

[nickleinonen]

Originally posted by HDerrick

I am having the the new just released 5 inch BD Power exhaust system installed tomorrow. I should have the details tomorrow night.

i have the BD 5" system on my truck. i like it pretty much. the fit of it was good [although i needed to tweek the downpipe hanger with a hammer a bit]. the bd system according to dean at bd is stainless, and it looks to be 409 [not mirror polished 304]. 409 is ok stainless for exhaust systems, but it will rust on the surface [there is no aluminumized protective coating on it like plain aluminumized exhaust] but i painted mine to avoid the rust. the muffler isn't quite flow through, there is a baffle in the inlet about 10" in that diverts most of the exhaust around the 5 about 2" pipes that feed the outer edges of the muffler. there are 5 or so 3/4" holes right in the middle of the baffle so there is some straight flow through [but that could be drilled out with like a 4. 5" holesaw] the sound at idle is nice, and under accelaration it sounds pretty good. the only droan i have noticed is when in 6th gear turning about 1000-1100 rpm lightly loaded. you can also hear almost like an exhaust leak under load, but i suspect it is the sound of the wastegate opening [or maybe the exhaust is swurling under my truck 'cause i didn't put the tip on the exhaust so it is a little short on the exit-not far enough away from the body]

 

[JDerbedrossian]

5 inch exhaust and afe without box did 222 hp on dyno SO model and 486 tq so i really dont see any losses in 5 inch unless my truck runs real good

 

[TheWolf]

So with the new boxes coming out (TST/Edge) and the trouble with temps that everyone has, do you still think 4" is enough for most people?? Or do you NEED 5" to help anywhere possible with the temps?





Thanks

 

[Wiredawg]

Running at 1000 to 1100 RPM?

nickleinonen



"only droan i have noticed is when in 6th gear turning about 1000-1100 rpm lightly loaded. "



Aren't you running pretty much below the power band of this motor? My 6-spd is on a 2d Gen ISB and it's BOMB'd pretty well, but I never run below 1. 800 except idling in 1st or 2nd in traffic.



Wiredawg