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Discussion Starter #1
Yesterday we took the plunge and removed the 159’s last cat and DPF.
After 100km all lights are still off and the car performs perfect.
Consumption already seems a lot better, performance definitely improved.
I will keep you posted.
The exhaust note did not change a lot. It basically sounds the same as what it used to during a regen.
This was a bit disappointing but since it is a diesel and an auto I suppose it is a good thing.
 

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Tell me more about the performance increase? What kind of increase, more pull, faster turbo spool? More top speed?
 

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Regional Representative, For South Africa - AO-SA
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:cool:
I am watching this thread with eagle eyes ...... before I take the plunge
I am also going for the De-Cat, getting it done by an exhaust guy that built my Junior's exhaust a few years ago.... rmoving both cats, straight pipe in place of one, and a smell silencer in place of the other..... apparently this is the majic recipy....

Did you takle any pics TN ? Where does the DPF live ?
 

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Discussion Starter #4
Power is a lot more.
First and second smoke tyre’s and that’s with the traction control on. Acceleration definitely improved and overtaking acceleration from 100km\h is a lot better than before.
The turbo spools faster and the boost also increased to about 1.55bar when you punch the pedal and then it is brought back by the ecu but that initial boost helps a lot.
Did a trip to JHB and the consumption improved with about 1km/l on average.
No need for a small box the car is so quiet you barely hear a difference.
After 200km still no warning lights so the management seem fine for now.
Regens are a problem since the probe that used to be between the main cat and the dpf does not see a rise in temp since the diesel dumped for the regen basically cools it of instead of burning around it to create more heat.

At least you can see when it regens now.:eek:
Switching off and restarting stops it but I definitely have to sort the software now.

Erick the DPF and second cat sit where the first 156 cats used to sit underneath the car.

If you replace all the oe cats and pipes I will suggest that you use 63 or 76mm pipe all the way from the turbo to where the cat / DPF stops. There you can taper the pipe off to the oe size. This will definitely help the turbo to spool a lot better.
We replaced the Cat / DPF with a straight pipe and fitted a pipe for the pressure sensor and rear EGT probe on it.
For now I can say that it is safe to remove the pre cat just behind the turbo. Let’s first see what we can work out regarding the regens before you do the rest. Unless you do not mind switching the car off and restarting when a regen occurs. Personally I do not like doing it.

Guili no idea about the top end I haven’t had her on a private road. But it will definitely be higher than what it used to be. No idea what it was to begin with? The one time that I did drive her like that I can say that she accelerated faster than a 156 2.5 all the way from 80 to Highway legal + almost 100 to his amazement.
He could live with the more power on the lower speeds (where I had to back off to keep from pushing him) but when I overtook him at that unmentionable speed he was absolutely amazed.
 

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Hhhmmm, forgive my diesel ignorance but what is regen?

And when you talk software do you mean remap? Dielels go like stink after a remap!

Saw a Xcede tuned X3 Diesel 3.0 run under 14 seconds at Tarlton!!!
 

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Discussion Starter #6
A regen is when the ecu dumps diesel into the outlet so that the soot deposits in the DPF can burn away.
It is an utterly stupid setup that increases your fuel consumption and robs the car of power.

What were the tree huggers thinking!!!!!

If you remove all of it the car actually saves the environment by burning less fossil fuel.
 

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Well if I really must inform you...the tree hugger are all talking heeps and heeps of kak. A cow's dung, or kak, polutes the air more than all our Alfa's combined!
 

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Discussion Starter #8
And still they keep on strangling the motors with Cats, DPF’s and other rubbish.
Spoke to a salesman at CMH a while ago and he stated that they are delaying all diesel imports because they had a lot of problems with the DPF’s on the 2.4.
Why don’t they just remove it and switch the regens of before they sell it? It’s so easy to do for them and will result in a reliable and economical car.
The other manufacturers bring diesels in without it why don’t Alfa.
 

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I take it in SA you don't need to keep the EGR and DPF handy for an annual test, but I heard that that may change? I thought it was possible to either cut the pipe and remove the dpf and re-weld, else remove section and push the DPF through the section. Then if you have a test, it all looks normal :) EGR valve is just permanently disabled in closed pos!

The ECU remap is needed I think. There's several in UK, maybe we should bulk buy, whatever format it comes in...:confused:

After all this will it effect Alfa's maintenance plan. They would probably be chuffed, several less things to bother with.
 

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Hi turbonutters,

I read you took off your DPF:thumbs:

Just give me a PM for turning off your regens now.
You remember...

tomsa
 

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Any updates on having the dpf removed?

Have you been able to turn of the regens in the software?

My 159 is nearing the end of its maintenance plan, so I am seriously considering having this done.

Anyone in SA doing remaps of these engines? I have been reading some good stuff about this but mostly in the UK.
 

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Regional Representative, For South Africa - AO-SA
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New DPF is around 18 k, I just bought a second hand one.
The problem with removal is the EGR Regen needs to be deleted from the software, and to date I do not know who can do this locally.
If you remove the DPF without EGR delete, you will get the engine warning lights every few hundred Kms :(
My car now has a brand new EGR, second hand DPF , once the DPF gets clogged, you are in for fun and games. My car went into limp mode and then completely shut down in the middle of nowhere two weeks ago.....:rant:

My tip, get it replaced under maint plan while you can........
 

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FR&R and STO do EGR and DPF delete and software update...call em.
 

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Regional Representative, For South Africa - AO-SA
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Phone numbers please Lance ?
 

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Normally I have nothing to add, but as an Alternative Energy (to include biodiesel) company owner, this is my something I know about.

SEGR (simulated EGR, read [email protected] the system) and DPF delete is the BEST thing you can do for a new diesel engine (regardless of make).

It will restore the reliability once associated with diesel engines. Allows use of vastly different fuels(don't ask unless you want to know) and makes engine friendly to numerous performance and/or efficiency mods
 
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