after market exhaust

[weldinfool]

I recently put edge w/attitude :D great mod on my 05 GMC next in line is an exhaust upgrade.this is where it gets fuzzy for me:confused:


aluminized vs 409 vs 309
single vs duals
catback vs turbo back
x brand vs y brand vs z brand
code eliminator........when do you need one:eek:
seems like the perverbial can o worms.
i know i want to lower egt and improve performance, along with improved sound, but what else is there to be gained or lost? is it worth the effort and expense?
I pull a travel trailer,alot, sometimes 800 miles plus.pull a boat and utility trailer,and i really like to see the look of some kid in a so called hot rod get waxed by a diesel 4x4 4 door truck:cool: love my ride but i think it could be a little better and i want to make it last at least untill its paid 4 so any and all input would be greatly apppreciated

[More Power]

The good exhaust system dealers who run what they sell will have a solution for EGR codes "if" yours is affected. Might be a good idea to ask first. Several of the vendors listed in the Advertisers Page (http://www.thedieselpage.com/vendors/main.htm) also offer exhaust systems. Give them a call... :)

Stainless or aluminized? Unless you detail the underside of your truck, they'll all look alike in a few weeks anyway. Each will last the same length of time (likely longer than you'll own the truck).

I'm considering going to a polished stainless shorty muffler and tailpipe on Lil Red (http://www.thedieselpage.com/features/project2-16.htm) just for the bling... :D

Jim

[Mark Craig]

weldinfool,

Well it depends on what truck you have LB7, LLY LBZ etc, not all of them need any foolers for the exhaust to stop a CEL, your signature didn't say what you had etc. Call us if you want, the discussion on aluminized, 409 and 304 can get really long and it really depends on you and how the truck is used and how long you intend to keep it etc. We stock all the MBRP and AFE systems in aluminized 409 and 304 and will be glad to help you.

Mark @ DPPI

[Kennedy]

Couple of quick comments:

Duals are loud. Regardless what anyone says they are loud. Also after seeing a set of MBRP duals smoke out the tailpipe joints while running open exit on the dyno, I'm not convinced that they are even equal to the performance of a single.

Cats hold heat. They also reduce flow. A full system is the best if you can get away with it. The Blocker pkg on my site will be necessary to nix codes if the cat is removed.

LLY Emissions:

http://www.kennedydiesel.com/docs/Duramax_LLY_Emissions.htm

Dyno proven performance:

http://www.kennedydiesel.com/photogal/pages/4-5exhaust_lly.htm

[JD_Diesel]

so how does the diablo work for the egr system?

[Bobo]

so how does the diablo work for the egr system?

I like the sound of Kennedy's exhaust on the LLY and LB7 the best.


Diablo turns the codes off so you can block the EGR.

[Mark Craig]

Kennedy,

Hey John, if they were leaking at the joints then the clamps were not tightened enough. As far as HP or EGT and or restriction on duals vs singles on dyno's that I have seen you can usually see a slight (very slight) EGT drop on duals as compared to singles. It's very, very difficult to verify and duplicate exactly each time but having done it quite a few times I am pretty convinced it's there! Now it's not enough to matter but it does show that at the very worse the duals and the singles are equal restriction wise. I didn't notice that they have been any louder either, just that you have volume from two sides vs just one. Which also happens to be so the driver can hear it better etc.

Mark @ DPPI

[JD_Diesel]

So if I unplug my egr and use my diablo setting for the egr well I still need to put the blocker plate in ? Thanks JD

[Kennedy]

The truck in question belongs to another shop owner so I'd expect that the clamps were tight. I dislike ubolt clamps as they do not seal.

All I had to do was start the truck on the dyno and I knew it was "loud" compared to others. My guess is that the amount of additional surface area just resonates more and can be "felt" in the vehicle.

[Kennedy]

So if I unplug my egr and use my diablo setting for the egr well I still need to put the blocker plate in ? Thanks JD

There are those who believe that the EGR will blow open, so they put the plate in as insurance. Personally, with a stock trans I don't see it happening and having made numerous dyno runs on my 2005 with big power I have seen no difference with the before/after.

[JD_Diesel]

Well thanks Mr Kennedy. I well unplug my egr this weeked and retune diablo to take care of the codes. Thanks for your help and service. JD

[martanius]

I am as fast as my buddies 2004. All I have is Edge /attitude. He has Banks exhaust and his truck sounds a lot better but to me it's not worth spending 800 bucks for 7HP... That's what he gained on the Dyno. Also his EGTs only dropped by like 150 degrees. My EGTs have never even hit 1000 with it on the #4 setting. I haven't pulled anything yet but when I do i'm only gonna be using the #1 setting so the temps should be fine there too. I'm thinking just swapping out my stock muffler will add some sound and allow more air flow. Should know more mid week. Had this truck 4 years and never did anything but drop in an K&N.. now I can't seem to stay off of EBAY.

[REDTRUCK05]

I was told that there was a allison upgrade for shifting. I was told that it bolted behind the tranny filter. Is this correct?

[mikel310]

weldinfool,

Well it depends on what truck you have LB7, LLY LBZ etc, not all of them need any foolers for the exhaust to stop a CEL, your signature didn't say what you had etc. Call us if you want, the discussion on aluminized, 409 and 304 can get really long and it really depends on you and how the truck is used and how long you intend to keep it etc. We stock all the MBRP and AFE systems in aluminized 409 and 304 and will be glad to help you.
Mark @ DPPI

As the above quotes states, it depends on how & most importantly where you use your truck & goes far beyond on how the exhaust ends up looking like.

Both my friend and I have boats which we drop into the ocean by trailer. He had aluminized & I have stainless. His truck exhaust is already showing signs of corrosion due to the salt water & will be replacing it very soon with stainless, and mine is still corrosion free, so just be aware of your usage.

Mike

[cowboywildbill]

Question? If I just remove the cat and keep the stock muffler and system in place on the 06 LBZ, will it help lower EGT's and will it be any louder? I am really spoiled with the quiet system on this new truck.

[mcwhitsitt]

John, are you saying if i go to a 4" exhaust and remove the cat I'll start getting malfunction codes??????????? '05 LLY / Allison Dually 3500

[BigO]

I have an 01 truck with no modifications. Just purchased a larger 5th wheel. The old 5th wheel ran around 9,250 lbs and this is 11,750lbs. Would a name brand 4" exhaust be needed? If the truck is not pulling it is sitting in the garage and driven every other weekend.

If I were to add exhaust, on an average, how much will the egt drops? What other benefits are there to adding exhaust? Why didn't GM do this from the start if this is better for our motors?

Thanks

[Kennedy]

John, are you saying if i go to a 4" exhaust and remove the cat I'll start getting malfunction codes??????????? '05 LLY / Allison Dually 3500

Yes.

Try reading here:

http://www.kennedydiesel.com/docs/Duramax_LLY_LBZ_Emissions.htm


The LBZ acts very similarly, but it's been my experience that regardless of emissions group it will likely set codes/SES light at some point.

[Melvin P. Thorpe]

The 4" turbo-back exhaust and AGE intake made a difference in temp's while towing on level #2. I pull some tall and steep mountains out here in the west so every 100 degrees is helpful. I can also hear the turbo spooling up around town and that is cool.

[jsmiracle]

I recently added a Magnaflow, turbo-back, 304 SS exhaust and installed lap joint band clamps at the joints instead on the included U-bolt type clamps.

I have noticed lower EGT's by about 100-200 degrees F around town. I am anxious to see the difference when towing the TT. I used to see as high as 1350F when towing up mountains.

The exhaust has not set the SES light, yet. I will check for codes in the next few days with the tuner. I am real happy with the exhaust and it seems to be a heavy gauge (sturdy) of SS.

I will let you guys know my observations when towing the TT.

Jim M.

[Mark Craig]

jsmiracle,

Hope this doesn't upset you as it's not intended that way at all. Magnaflow doesn't have a 304 system, they use 409 and 436. Lots of their dealers/jobbers say it's 304 but it's not. Hope this doesn't ruin your afternoon.

Mark @ DPPI

[Mark Craig]

Question? If I just remove the cat and keep the stock muffler and system in place on the 06 LBZ, will it help lower EGT's and will it be any louder? I am really spoiled with the quiet system on this new truck.
cowboywildbill,

Yes it will lower EGT's but you are waaaaay better off getting a cat back system and leaving the cat alone. You'll get more EGT drop and if the cat is in place the cruising sound level will be very very close to stock, when you wail on it it'll wake up some but is not loud to most folks. If you pull the cat it'll be louder and the EGT's will drop even more.

Mark @ DPPI

[Mark Craig]

I have an 01 truck with no modifications. Just purchased a larger 5th wheel. The old 5th wheel ran around 9,250 lbs and this is 11,750lbs. Would a name brand 4" exhaust be needed? If the truck is not pulling it is sitting in the garage and driven every other weekend.

If I were to add exhaust, on an average, how much will the egt drops? What other benefits are there to adding exhaust? Why didn't GM do this from the start if this is better for our motors?

Thanks

BigO,

The turbo will spool up sooner and the EGT will drop as well as a nicer deeper tone are the benefits. The factory does what they have to do make the stock truck operate to a level that they want to advertise it at, nothing more or less.

Mark @ DPPI

[jsmiracle]

jsmiracle,

Hope this doesn't upset you as it's not intended that way at all. Magnaflow doesn't have a 304 system, they use 409 and 436. Lots of their dealers/jobbers say it's 304 but it's not. Hope this doesn't ruin your afternoon.

Mark @ DPPI
Mark,

:o Thank you (sincerely) for your correction. I knew I'd made a mistake soon after I hit the "reply" button.

It is a 409 SS system. As an additional detail..... I was looking at the more expensive system with the polished tip and muffller which I thought was a 304 SS system. USDieselParts.com (found from TDP's advertisers) recommended Magnaflow's XL system which lacks the polished tip and muffler, but saved me another $200. They told me both systems were made of 409 SS. They knew I was after function over "looks". It was a very good purchase experience and I am very happy with the exhaust system.

I figured someone on this forum would notice my error in grades of SS. Frankly, I am pleased someone did....thanks.

Take care,
Jim M.

[Mark Craig]

jsmiracle,

WHEEE good hoped you'd take it that way. Yep lots of "dis" and "mis" information out there on lots of products and when I see it I try to correct it as it's here for eternity and others will get confused etc!!

Glad you got what you expected and all is good!!

Mark @ DPPI

[titanite]

I am as fast as my buddies 2004. All I have is Edge /attitude. He has Banks exhaust and his truck sounds a lot better but to me it's not worth spending 800 bucks for 7HP... That's what he gained on the Dyno. Also his EGTs only dropped by like 150 degrees. My EGTs have never even hit 1000 with it on the #4 setting. I haven't pulled anything yet but when I do i'm only gonna be using the #1 setting so the temps should be fine there too. I'm thinking just swapping out my stock muffler will add some sound and allow more air flow. Should know more mid week. Had this truck 4 years and never did anything but drop in an K&N.. now I can't seem to stay off of EBAY.


Martanius, did you try this out?? Any success? After looking over the exhaust the muffler (stock) seems to be the biggest restriction. Would be interested in what happened if you just replaced that boat anchor of a muffler with something that allows gases to flow with less restriction.

[FourMoCajuns]

Martanius, did you try this out?? Any success? After looking over the exhaust the muffler (stock) seems to be the biggest restriction. Would be interested in what happened if you just replaced that boat anchor of a muffler with something that allows gases to flow with less restriction.


Yes I was thinking the same here.

[MagnaFlowRep]

Mark,

:o Thank you (sincerely) for your correction. I knew I'd made a mistake soon after I hit the "reply" button.

It is a 409 SS system. As an additional detail..... I was looking at the more expensive system with the polished tip and muffller which I thought was a 304 SS system. USDieselParts.com (found from TDP's advertisers) recommended Magnaflow's XL system which lacks the polished tip and muffler, but saved me another $200. They told me both systems were made of 409 SS. They knew I was after function over "looks". It was a very good purchase experience and I am very happy with the exhaust system.

I figured someone on this forum would notice my error in grades of SS. Frankly, I am pleased someone did....thanks.

Take care,
Jim M.

Our XL Kits Come with a Non Polished Muffler and a 5"Single Wall Tip
Our Pro-Series doesnt come with a Polished Muffler and No Tip.
All of our systems are 409 Stainless on the piping. 432 on the mufflers and 304 on the tips.
The reason we dont use 304 on our piping is due to the fact that 304 once its heated up and then cools down it becomes very brittle. And then the hangers break off. So thats why we use the 409 alot stronger.

[moss6]

:confused: This is such an intriguing subject; the exhaust system of a diesel engine, as uncomplicated as it; in reality should be, has in the hands of the EPA and the manufacturers become an enormously complicated and overgrown nightmare. If asked thirty years ago, what an engineer thought of how good it would be to force an engine to ingest its own exhaust gasses back into the intake tract; he would most probably believe that they had lost their fricken mind and should be in search of some good professional help or be locked up. I think I can see Al Gore asking that question.
Being an owner of one of these marvels of creativeness, and also probably being extremely simple and environmently primative, I'd love to make some changes, but would hate to face being terminally incarcerated for my 'hands on' alterations of my personal property. By the way, I also smoke; so I can see with the logical progression of our lib society that sometime soon I can expect to be outfitted with my own personal exhaust system should I not change my ways. I would add that I suspect those aflicted with flatuance are on the radar also; you are a danger to the planet as you are killing our ozone layer. Seems the older ones and bikers are the chief offenders according to the reports that I have seen. And by the way, why is it that the Harleys are immune to converters and EGR systems?
My my I have so gotten off track; I do have questions.
I am in total agreement with Kennedy's assesment of the EGR system; it is a crime to so intentionally degrade the life and performance of an excellent diesel powerplant like the Duramax engine. I wonder if it wouldn't be possible to not only isolate the EGR tract from the exhaust but also create another fresh air supply upstream from the MAF to take the place of the exhaust gas reinjection function. This would allow the EGR valve to function as intended and also replicate the change to the MAF. The two great benefits would be that the engine no longer inhales the trash but moreso that the new fresh air would be cooled by the less loaded intercooler. This of course would not be possible if the system is not capable of drawing that air on its own----I'm not sure, I need to do some tear down to better understand whats going on. Could be someones tried something like this and can educate me.
I really hate the EGR------
Any feedback is greatly appreciated.

[tufcj]

I have an 03 LB7. I've been looking at the Magnaflow turbo-back systems. Any down sides to the turbo-back vs. just a downpipe-back system?

The truck is mostly just a daily driver with maybe 5K miles per year pulling a 7-10K enclosed trailer.

Thanks,

Bob
tufcj

[More Power]

I have an 03 LB7. I've been looking at the Magnaflow turbo-back systems. Any down sides to the turbo-back vs. just a downpipe-back system?

The truck is mostly just a daily driver with maybe 5K miles per year pulling a 7-10K enclosed trailer.

Thanks,

Bob
tufcj

Bob, Only those who are seeking to wring out every last horsepower will likely want to step up to a turbo back system (more tedious to install, less clearance, etc.). The downpipe or cat-back systems just make the most sense for most people.

Jim