DW8 vs XUD

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20th Century Pug
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DW8 vs XUD

Post by 20th Century Pug »

Been searching the forum posts for info about the DW8. I am interested to learn what tech advances Peugeot made when they superseded the XUD with the DW8? As far as I can tell, they are similar. Change to dry liners and repositioned glow plugs and the addition of EGR & cat. The basic architecture appears to be the same. However, in my experience the DW8 has very noticeable increase in performance, and wondering how I could apply that to my XUD. Is there a change in the swirl chamber shape for improved combustion? Or is it to do with the manifolds and injection pump?

My 305 estate will return approx 45mpg around town, 48 - 52mpg on a run. I ran a 99model 206 for six months. A similar size car, albeit more streamlined shape. That had the DW8 engine. Performance was more lively and it returned 55 - 60 mpg. I was expecting the EGR to decrease performance! However, I am not certain the EGR was actually working as the valve had a load of black gunk inside. Some earlier posts suggest it can be troublesome.

Thanks
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Huskyxantia
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Re: DW8 vs XUD

Post by Huskyxantia »

The dw engines are more refined less noise but a little bit more pipe work than thd xud, egr stuff and so on, dw feel like a larger petrol the xud feel like real old diesel
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Re: DW8 vs XUD

Post by Huskyxantia »

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Re: DW8 vs XUD

Post by 20th Century Pug »

Thanks for the useful links. I note that the inlet manifold and intake system are different, also that the head has 'Advanced Comet Ricardo latest technology precombustion chamber'. So is this 'latest' design of swirl chamber the main improvement over the XUD? Does this mean that the injection pump has revised metering and advancement characteristics? What about the valve timing?

Does anyone know if a DW8 head will fit an XUD block? Just thinking this could be a relatively simple way to get a worthwhile improvement in economy with an XUD engine car without the wiring and ECU issues of a full HDi.

Anyway, just a thought. :idea:
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Huskyxantia
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Re: DW8 vs XUD

Post by Huskyxantia »

Would the new engine be like a frankenstien moment ! lol
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Re: DW8 vs XUD

Post by 20th Century Pug »

Maybe. Just trying to find out if it's possible - like are the hole centres the same?