Alfa Romeo 2.4 JTD-m DPF removal and homebrew tuning

[jammapic]

Hi,

Many of you will know that for a good few years now I have been (relatively secretly!!) running my own tuning company. It all started back when I had my own VW Golf 1.9 TDi 110 (non-pd) and I got the bug for ECU's, tuning and how the whole electronic system works. Fast forward 9 years and a whole host of diesel cars from Peugeots through the BMWs and I've tuned every single one.

This brought me more recently to tuning for the public, through www.facebook.com/tdiremaps and www.tdiremaps.co.uk. We specialise in PD engine'd stuff mostly - with the cars being relatively affordable and responding very well to tuning.

Anyway - enough of that for the moment, and more another time (as I have many of these project articles backed up!!!)...

At the weekend, I tuned an interesting car... our fellow admin, Brynllwynog2's Alfa Romeo 159 2.4 JTD-m. He bought this car a few months ago before we went to the Nurburgring, as a comfortable cruiser, which actually (after a few fixes to broken things, like a MAF sensor, swirl flaps, gummed EGR etc) well relatively well for a big car - and joined the sub 10 minute club in totally standard trim.



When we got back - I was asked if we could make it go a little better... Having never worked on a 2.4 JTD-m, it should have been all new to me; but I quickly realised that it was almost exactly the same as the 1.9 JTD (or 1.9 CDTi in the Vauxhall / Opel chassis) and I have tuned a LOT of these.

First job was to read the file from it, and study it. We did that using MPPS, as the ECU is EDC16 - it's simple. File loaded into WinOLS I found that it was fairly different to the 1.9 CDTi's I had tuned before, but with the same concepts in place. Meaning, with a little educated guessing and some light mods I was happy we could breath a bit more pep into the big 5 pot.

I spent a few hours going through all the changes, checking it was as I thought it should be and we loaded on the stage 1 tune.

I am always confident with all the cars that I tune, that 30hp gain and 50lbft is fairly achievable on a stock engine, so I was happy the car would go a lot better and should still be DPF (particulate filter) friendly.

We took the car out for a spin, and immediately we could feel it was a lot more urgent and a lot more responsive.

When we got back to the workshop I did another version 2 file, with a bit more torque in places, and some more map modifications to improve the fuel economy - as these engines are well known to be fairly thirsty!

I left the car tuned at around 230hp and 380lbft knowing it would be safe.

Fast forward a few months - and the car has been faultless. With Brynllwynog2 doing a good few thousand miles, reporting better economy and much more pleasant driving experience... but he wanted more.

We knew any more tuning would require the particulate filter to come out, and given the catalytic converter is built into the same box - we thought we would hollow the whole thing out, and make an MOT friendly, straight through pipe.

When we took the DPF off, we found this....



It just shows why, even when driving long distances and allowing the ECU to regenerate the DPF as and when it wants - there is no better option than to remove it. They DO, clog up. I myself drive an Astra CDTi, totally stock company car - and it has had to go back to the dealer no less than 3 times now for forced regen and solvent bath to clean it out. They are rubbish!!

Queue a great big drill and a crow bar:



and after 30 minutes or so of persuasion...

tada!



After this - we created a "DPF off" map for the car with exactly the same fuelling and boost parameters dialled in as before. We could feel the car was much more keen to pick up, much happier to rev and really felt like it would take quite a bit more power.

So we headed down to the dyno and set to work on a new version of the file. I added some boost, added some fuel and fettled the various limiters and timing maps needed to make it run right.

We spun it up on the dyno and were pretty amazed at the result we saw...



Thats 271.1hp and 457lbft!! I was a little concerned that the map was a bit "lumpy" but we have since rectified this by modifying the turbo actuator control maps as we found we were getting a little bit of boost surge when rolling on the throttle too hard.

This car will never be finished. We all know how these projects work. Brynllwynog2 will fit some extra hardware, no matter how big or small and I will write a new map. Will will no doubt keep searching for that illusive extra 1hp until we find a limitation, and then change it.

I can't help thinking 300hp is tantilisingly close....

Keep an eye here on the forum, and on http://www.facebook.com/tdiremaps for more updates.

JP

[Piggy]

Cracking engines these!

Glad to see one given some decent treatment and see the potential!! Awesome

[jammapic]

Next time Chris is over I will get it on the dyno again, and with more fuel pressure it's making a chunk more torque through the midrange and a sniff more boost at the top end it might gain a couple of bhp.

I am going to look at getting a hybrid turbo built up - as it's currently boosting just under 1.7bar which looking at the compressor map is right on the limit.

The injectors are pretty big, as the durations aren't particularly long so I think with 2bar on a decently sized unit it will run well into the 300's.....

[Piggy]

isnt it a GTB2056? 28psi is peak on those isnt it?

[jammapic]

No its the kkk unit on this. The shitter one. Lol

[Piggy]

oh that sucks, get the GTB20 or 22 on it. 300bhp easy then!

[jammapic]

That's the plan

[Seb_Ryan]

Its a gtb2260 (I think its the b) on the 20vs, ive only got the baby gt2256v on my 10v one lol, the torque is pretty immense on these 5 cylinders I gotta be fair.

But yeah the 10v is a 1.9 8v gm engine with another cylinder and the 20v is the 1.9 16v

Get on the alfa forum JP, Theres not many that have proper pushed things with these.

[jammapic]

Nah, I can't join the Alfa forum as I don't own one... I'm just the tuner! :p

[swampy]

Hmm interesting

I know the engine in the 156 is a lower state of tune , but how much different is the actual map?

If we keep the car in to the new year I may well be interested

[jammapic]

I can always have a look.....

[JTaylor2005]

Hi guys going to drag up a bit of an old thread here I am just wondering whether you had the swirl flaps removed or just fixed them and made sure they worked? My car really lags below 2000rpm and I'm thinking it's probably being caused by clogged intake flaps and egr valve.

Nice work on the tuning! 270hp is damn good from these engines

[toseland]

Wonder if one of these would fit in a 306.. they sound mental with a straight through

[JTaylor2005]

Haha I'd be amazed if it did

[welshpug]

anything can be made to fit.