Peugeot XUD9

[nokivasara]

I have a Pug Expert van with the wonderful XUD9 engine. Iīve had the smoke screw turned in quite a bit but have backed it off to the original setting again, mainly because the mileage suffered from it, going from 7.2l/100km to 8.5l/100km  :shock:
Anyway, I still have the boost pin at the most agressive setting and with stock boost itīs not smoking at all, not even lightly. In my world that means thereīs too much unused oxygen in the combustion which means I can increase the fueling a bit to get more power without loosing too much of my mileage. Right or wrong?

I noticed that the boost pin still has about 5mm of travel before it bottoms out.
Should I look for a softer spring or turn the star wheel? I donīt really understand the function of the starwheel...
I also donīt think that turning the smoke screw is the way to go since it only sets the starting point of the boost pin travel, the more itīs turned in the shorter the overall travel, right?

If I just increase the boost it will increase the travel of the pin but it would still be a super lean mixture.
Should I run stock boost, 0.9bar, with light smoke or higher boost, maybe 1.1-1.2bar and no smoke?

[dillenger1]

if you turn in the smoke screw you get less travel,but it starts at a "more fuel"setting.The star wheel sets preload on the boost pin spring.the further down youy screw it the less boost needed to move it,unscrewing tightens the spring and will require more boost to get the pin moving.

[nokivasara]

Iīve been fine tuning the Van lately and I think Iīm close to the perfect settings  
Itīs my daily driver/commuter so the mileage is important.

This is what Iīve ended up with:
1. max fuel screw about 1/4 turn in, had it @3/4 turns but got some smoke
2. Boost pin in most aggressive setting
3. Star wheel one turn in (no difference, need to turn it down some more)

That's it, the boost is at 1.1 bar, it has incresed by itself along with increased fueling.

This moderate tune gives decent, very noticeable, increase in power with no loss in mileage and most importantly (for me) no smoke!