Duramax Diesel Exhaust Mods, and Stuff*

[Black02Silverado]

PLAN B!

-Retain the Cat. Retaining the Cat Converter will take all the stank out of the exhaust. i was not aware of the separate catalyst on these trucks. I am a big fan of DOCs. I sold a ton of them, and they really clean up the exhaust, and have little to no restriction. I can get a Cat Back stainless system, with a resonator, and will sound good, look stock-ish, and burn even cleaner without that eye-burning stank.

Stock cat piping is like 2.5"...

But with the cat still in, just the DPF out, I put 468hp and 850lb-ft to the ground...

Is it really that small?? Shit. Man, I really want to run a DOC. I suppose I could get a 4 incher, but they are like $800.

I also ordered a roll of 307 stainless wire so I can weld it all in, and ditch those stupid looking clamps.

Might be 3" but I'm pretty sure it swedges down to 2.5 in there.

That's just crazy. You would think GM would want it to breathe better and put a nice size exhaust in there to get the performance gains without adding much to the cost


Sent from my MaxiPad

 

[PenguinLTZ]

PLAN B!

-Retain the Cat. Retaining the Cat Converter will take all the stank out of the exhaust. i was not aware of the separate catalyst on these trucks. I am a big fan of DOCs. I sold a ton of them, and they really clean up the exhaust, and have little to no restriction. I can get a Cat Back stainless system, with a resonator, and will sound good, look stock-ish, and burn even cleaner without that eye-burning stank.

Stock cat piping is like 2.5"...

But with the cat still in, just the DPF out, I put 468hp and 850lb-ft to the ground...

Is it really that small?? Shit. Man, I really want to run a DOC. I suppose I could get a 4 incher, but they are like $800.

I also ordered a roll of 307 stainless wire so I can weld it all in, and ditch those stupid looking clamps.

Might be 3" but I'm pretty sure it swedges down to 2.5 in there.

That's just crazy. You would think GM would want it to breathe better and put a nice size exhaust in there to get the performance gains without adding much to the cost


Sent from my MaxiPad

I have been doing a lot of reading. Many people are doing this, as it significantly cuts down on the smell, and the burning eyes. You are just limited to how much power you can put down, and less mileage on the higher HP tunes. I think I am going to do it.

 

[drperry]

PLAN B!

-Retain the Cat. Retaining the Cat Converter will take all the stank out of the exhaust. i was not aware of the separate catalyst on these trucks. I am a big fan of DOCs. I sold a ton of them, and they really clean up the exhaust, and have little to no restriction. I can get a Cat Back stainless system, with a resonator, and will sound good, look stock-ish, and burn even cleaner without that eye-burning stank.

Stock cat piping is like 2.5"...

But with the cat still in, just the DPF out, I put 468hp and 850lb-ft to the ground...

Is it really that small?? Shit. Man, I really want to run a DOC. I suppose I could get a 4 incher, but they are like $800.

I also ordered a roll of 307 stainless wire so I can weld it all in, and ditch those stupid looking clamps.

Might be 3" but I'm pretty sure it swedges down to 2.5 in there.

That's just crazy. You would think GM would want it to breathe better and put a nice size exhaust in there to get the performance gains without adding much to the cost


Sent from my MaxiPad

I have been doing a lot of reading. Many people are doing this, as it significantly cuts down on the smell, and the burning eyes. You are just limited to how much power you can put down, and less mileage on the higher HP tunes. I think I am going to do it.

For what you're looking for out of it, you'll be fine. Mileage will still be better than with the DPF. Put in a new down pipe, keep the cat, and you'll have a decent drop in EGTs, quicker spool, and honestly, you'll never notice it's there unless you look underneath.


I want full potato mode, so it wasn't an option for me, lol.

Myself, I only really notice the exhaust when it's running indoors.

I wonder what it is about the V8s that make the smell... Fords have a worse smell... But I've never noticed anything from my friends 5.9

 

[PenguinLTZ]

Shipped back the full system, have the cat-back on the way.

I can always change it later if I tune for more power, which I doubt I will.

They all reek, even the inlines

 

[drperry]

You'll be plenty happy with it

 

[PenguinLTZ]

Oh yeah. I am going to have to pull the big load I have tomorrow as a stocker

I might just use the Ford. I feel so much more stable in my truck pulling 20K, though.

 

[drperry]

Oh yeah. I am going to have to pull the big load I have tomorrow as a stocker

I might just use the Ford. I feel so much more stable in my truck pulling 20K, though.

In stock trim, those 6.7s are pretty beastly... I haven't towed with one, but even the 550s at work don't seem as composed with the same load, as my 3500 does, lol.

 

[PenguinLTZ]

Oh yeah. I am going to have to pull the big load I have tomorrow as a stocker

I might just use the Ford. I feel so much more stable in my truck pulling 20K, though.

In stock trim, those 6.7s are pretty beastly... I haven't towed with one, but even the 550s at work don't seem as composed with the same load, as my 3500 does, lol.

I am not sure what the stock numbers are on my 2014 F250 vs my 2015.5 2500HD, but I have towed the exact same load, up the exact same hills, 16K, 12K, and 10K and I can say without a doubt the GM gets up the mountain quicker. The exhaust brakes are about even. They both have bags, but my GM is much more comfy with a load. The Ford feels light on the front end, no matter how much more air I put in the bags.

The Ford even has a manifold pressure gauge, so I know the engine is doing all that it can.

 

[drperry]

Oh yeah. I am going to have to pull the big load I have tomorrow as a stocker

I might just use the Ford. I feel so much more stable in my truck pulling 20K, though.

In stock trim, those 6.7s are pretty beastly... I haven't towed with one, but even the 550s at work don't seem as composed with the same load, as my 3500 does, lol.

I am not sure what the stock numbers are on my 2014 F250 vs my 2015.5 2500HD, but I have towed the exact same load, up the exact same hills, 16K, 12K, and 10K and I can say without a doubt the GM gets up the mountain quicker. The exhaust brakes are about even. They both have bags, but my GM is much more comfy with a load. The Ford feels light on the front end, no matter how much more air I put in the bags.

The Ford even has a manifold pressure gauge, so I know the engine is doing all that it can.

Run the front axles over a scale, lol. Maybe the weight just isn't transferring as well in the Ford... Or the engine is lighter, lol.

Do Fords still run the beam?

 

[drperry]

Driving a stock LML for a week or two... fWONk this thing is a turd [emoji38]