Pajero Owners Club of South Africa

As most might be aware I, along with the assistance of other owners, have (frustratingly) been trying to put my finger on the main reason for the performance issue of the '07 to '09 Pajero 3.2 DID common rail motors. This issue is most noticeable at about 120 kph and most obvious when towing, overtaking, uphill, etc. I just find it unbelievable that something seemingly so mechanically perfect can be so elusive and "unco-opperative" re finding a solution. I label it as a performance issue but fuel consumption is my main driving factor. IE - if you don't use the performance you will benefit from the fuel economy. So it is a win win situation no matter how you drive.

I believe I have exhausted all other possibilities (see thread Early (2007-'09) Gen4 cruising performance and fuel consumption). So I decided to start a new thread as I am looking at a new area ie the exhaust system. Reading up on other forums local and Australian there is a lot of discussion and positive comment re improving the exhaust system. Maybe someone can post some links - please CATS. (I was BBC). Remember that our vehicles are not exactly the same though. We do not have Diesel Particulate Filters, VGT turbo's, or swirl type inlet manifolds in our (NS) pajero's. We do have Catalytic converters.

Now I am not proposing that we rip our exhaust systems out. It does appear that the first section of the exhaust that actually houses the Catalytic converter is responsible for creating turbulance and obviously restriction. This makes sense as the performance loss is when the turbo is at full boost and I expect the waste gate is dumping excess exhaust pressure into this same pipe creating turbulance.

I am willing (as a test ) to replace this section with a freeflow section which I am trying to source. These are also fitted on 3.2 Tritons as well. Evidently de Graaf in Pta north made these sections but now only make up complete systems. Can anyone help / does anyone know of someone who could assist (know who owns a 3.2 triton with free flow ?). Once we are sure if this is the solution we can make a group plan.

Hi, thank you for accepting me on the forum.

I have a 2007 swb pajero 3.2 DID auto. It has 230000km on the clock. I bought it second hand two years ago. With 158000km. My fuel consumption on open road was around 8.9-9.4l/100km. (Tyers: Bridgestone dueler h/t). I then switched to wranglers a/t which dropped the consumption with about 1l/100km. I more recenty found a drop in general power and consumption. I read the previous thread to aid in my decision on what to do.

I went and removed the catalytic converters at a local exhaust shop. Basically manufacturing new down pipe and pipe where the second cat was. It's not the prettiest conversion but was only R1200 for the job. I then went to Dastek and put in a basic Unichip. (mind blown) the dyno report showed around 10 b.h.p increase throughout. Max power being at 3500rpm @ 134.5 b.h.p

What I noticed was:

Much smoother gear changes.
Better throttle response
A noticeable increase in power right through.
(Even my wive felt the difference)

As you would expect I have not tested the fuel consumption as I'm still "testing" all the power.
We are going to Mozambique next week and will give feedback on the power and consumption when loaded.

I hope this helps in the matter

Is there any chance you might still have the down pipe /cat that they removed ?. This is what is needed to copy the flange and make up the down pipe.

They cut off the cat and added a piece off pipe where the cat was, using the old flange. They manufactured the bends etc to fit. Hope this pic will help.
If you to to any exhaust shop, you can just ask them to remove the cats. They will ad in pipe where the cats was.

Thanks for the photo now I can explain the theory. It is claimed that the section shown causes the most restriction due to the fact that two pressures from the turbo (normal plus waste gate at full boost) are being pumped into this area. Evidently the answer is to seperate the two here with a specially made laser cut flange on which the two manufactured pipes are mounted and then branch / join the second in lower down just before the flange. This bolts onto the std system. If this theory works it is a simple bolt off / bolt on action. We can then get someone to make up these for everyone.

Uys, in the 4x4 Community forum, has the ability and design tools to take on such a project. I recommend you contact him and see what his opinion is.

Thanks for that info Roelf. I do think we must do some homework first though before we go that route. I would not want to go to a lot of expense to find out it is not successful.

So if anyone has such a pipe (or knows some one eg who is trading a vehicle in (we can even swop - just the front Cat section) from a Gen4.1 (I believe 3.2 Triton might be the same too) I will hand make the flanges and pipes for a test unit. I just need the section to make a jig for the shape and copy the flange from. It would take a few days. We can then see if it is worth while or not. Unfortunately my vehicle is in daily use and I cannot immobilise it.