Free-Flow Catalytic Converter

C

Cutlercollin99

Member
Joined
Jan 10, 2017
Location
Southern Utah
TDI
2004 beige VW Jetta TDI and 2014 Passat TDI
Hello all,

I was wondering where free-flow catalytic converts are available to purchase and if any of you guys have free-flow catalytic converters on your TDI's. Searching google and this forum didn't pull up any specific product. I have a 2014 Passat TDI and am looking for one to gain more mpg. Does this exist?

Thank you guys
 
jackbombay

jackbombay

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Mar 12, 2002
Location
Diesel knows best
TDI
A4 Jetta
Cutlercollin99 said:
Hello all,
I was wondering where free-flow catalytic converts are available to purchase and if any of you guys have free-flow catalytic converters on your TDI's. Searching google and this forum didn't pull up any specific product. I have a 2014 Passat TDI and am looking for one to gain more mpg. Does this exist?
Thank you guys
Click to expand...
Your catalytic converter does not reduce your MPGs in any measurable way.
 
oilhammer

oilhammer

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outside St Louis, MO
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There are just too many to list....
You need to read about and understand all your car's emissions control systems, and then you will perhaps see why your question has no merit.

You'd have to DELETE it all, change software (this is not only illegal, but it will void any Dieselgate warranty coverage) and you may gain a few MPGs average.

There is FAR more to the emission control system on that car than a catalytic converter, and the [several] parts that are on the car now do not limit "flow" in any way that is going to change fuel consumption.

It is a big car that is already capable of using less fuel than just about anything in its class. Enjoy it!
 
turbobrick240

turbobrick240

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maine
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2011 vw golf tdi(gone to greener pastures), 2001 ford f250 powerstroke
^ I was thinking the same thing. That passat has several catalysts, a particulate filter, etc. The only exhaust component you can just chop off and replace willy-nilly is the muffler.
 
oilhammer

oilhammer

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outside St Louis, MO
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There are just too many to list....
jackbombay said:
My TDI Vanagon had no cat for many miles, I track every fill up in a fuel log. I added a cat to the exhaust system and put many more miles on the vehicle and there was ZERO difference in the MPGs.
Click to expand...

Great. Has nothing to do with a CKRA engine, but great. ;)
 
oilhammer

oilhammer

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outside St Louis, MO
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There are just too many to list....
I think the whole thing flew right over your head. You may be in the same arena of understanding as the OP regarding modern diesels and emissions control systems. Maybe both of you need to take a gander underheath an NMS equipped with the CKRA engine to get an idea of just how much is going on under there. It is not, at all, like a VE or PD TDI (regardless of where it may be currently residing). ;)

However, because I DO understand them, I will stand by every word of my statement made in post #2, including the part about doing an [illegal] delete on ALL those components (since you cannot single out just a catalyst) and subsequent software modifications (again, quite illegal) and then the engine WILL use less fuel because it is not beholden to keeping those said removed exhaust emissions components functioning (which, require fuel to function). DPFs regenerate by being fed via an overfueled engine.
 
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jackbombay

jackbombay

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Diesel knows best
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A4 Jetta
oilhammer said:
I think the whole thing flew right over your head. You may be in the same arena of understanding as the OP regarding modern diesels and emissions control systems. Maybe both of you need to take a gander underheath an NMS equipped with the CKRA engine to get an idea of just how much is going on under there. It is not, at all, like a VE or PD TDI (regardless of where it may be currently residing). ;)

However, because I DO understand them, I will stand by every word of my statement made in post #2, including the part about doing an [illegal] delete on ALL those components (since you cannot single out just a catalyst) and subsequent software modifications (again, quite illegal) and then the engine WILL use less fuel because it is not beholden to keeping those said removed exhaust emissions components functioning (which, require fuel to function). DPFs regenerate by being fed via an overfueled engine.
Click to expand...

The subject of this thread is replacing the cat with a high flow version to gain MPGs. No mention of the DPF, or its removal, was made in the original post.


You are talking about MPG gains from *removing* the DPF, but that is not the subject of this thread.
 
oilhammer

oilhammer

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outside St Louis, MO
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There are just too many to list....
The catalyst IS PART OF THE DPF!!!! :p :rolleyes: :D

The OP's original premise was flawed. You've merely piled more on top of it.

I am done here. Have fun!
 
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Matt-98AHU

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Oilhammer's right... these systems are far too complex to just swap out another part and hoping for a gain. They're all interconnected and work together. And it doesn't have just one cat, it has multiple.

It has a diesel oxidation cat that's part of the DPF assembly. The DPF itself has a similar coating to its substrate as the DOC so it too is partly operating as an oxidation catalyst. Further downstream there's the adblue injector going into the selective catalytic reduction cats... that's right, more cats! Of a very specific and special kind!

There is no just swapping on some special high performance catalyst on these. They don't exist and anything you do to the factory emissions equipment in that vain are not going to gain you anything.

The only gains you'll ever get are from removing ALL of the components and retuning the car to operate without those emissions devices. It's the programmed operation of the engine where it literally is burning more fuel than is necessary to only propel the car in order to keep emissions in spec is the reason why they're not as efficient as they COULD be.

The only real gains you'll see in efficiency is by removing ALL of the emissions hardware and reprogramming the engine computer accordingly, as Oilhammer mentioned. And, as he also mentioned, that is an illegal thing to do...

These cars don't have a simple diesel oxidation catalyst all by itself like older diesels do...
 
jackbombay

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oilhammer said:
The catalyst IS PART OF THE DPF!!!!
Click to expand...
Me and George Bush have one thing in common, we both received bad intel.

Matt-98AHU said:
Oilhammer's right... these systems are far too complex to just swap out another part and hoping for a gain. They're all interconnected and work together. And it doesn't have just one cat, it has multiple.

It has a diesel oxidation cat that's part of the DPF assembly. The DPF itself has a similar coating to its substrate as the DOC so it too is partly operating as an oxidation catalyst. Further downstream there's the adblue injector going into the selective catalytic reduction cats... that's right, more cats! Of a very specific and special kind!

There is no just swapping on some special high performance catalyst on these. They don't exist and anything you do to the factory emissions equipment in that vain are not going to gain you anything.

The only gains you'll ever get are from removing ALL of the components and retuning the car to operate without those emissions devices. It's the programmed operation of the engine where it literally is burning more fuel than is necessary to only propel the car in order to keep emissions in spec is the reason why they're not as efficient as they COULD be.

The only real gains you'll see in efficiency is by removing ALL of the emissions hardware and reprogramming the engine computer accordingly, as Oilhammer mentioned. And, as he also mentioned, that is an illegal thing to do...

These cars don't have a simple diesel oxidation catalyst all by itself like older diesels do...
Click to expand...
Thanks for a rundown of how the system works!
 
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