1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot down?

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kenbw2
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Re: 1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot d

Post by kenbw2 » 08 Jan 2018, 01:22

MikeT wrote:
07 Jan 2018, 19:24

No, not just the top end, the whole accelerator range.
Think of the trigger gun held at 50% open; when you open the standing pipe tap more fully, more water will flow out the gun without moving the trigger.
Numbers might not make sense maybe, but bear with me.
The standing pipe tap at 50%, and the trigger at 50% gives x litres/min
With the standing pipe at 70% and the trigger at 30%, that would give the same litres/min

The only benefit comes in when the throttle (trigger) is at 100%, that would get more output with the max fuel screw (standing pipe tap) at 70% than 50%

Would that be right?
MikeT wrote:
07 Jan 2018, 19:24
Yes, there are many settings that affect others and these need to be balanced to obtain the best tune. The factory setting not only needs to take power into account but engine longevity, emissions, passenger comfort and noise outputs too. changing one compromises others, as already advised by other posters.


Good points. Factory settings are a bit irrelevant in my case because my pump is from a 306 XUD9, and is now on a Dispatch DW8. The garage have done whatever tunings they've done, but I don't know it's optimal.
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Re: 1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot d

Post by MikeT » 08 Jan 2018, 15:20

Ok, I think we're on the same page, I wasn't sure earlier. It's also been quite a while since I've played with a Bosch pump, are all DW8's turbocharged? Tweaking the LDA alone (the add-on that controls extra fuelling to match the compressed air) can give impressive results.
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kenbw2
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1994 Peugeot 106 1.5D: seen better days
1996 Peugeot 106 1.5D: cremated
x 8

Re: 1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot d

Post by kenbw2 » 08 Jan 2018, 15:32

MikeT wrote:
08 Jan 2018, 15:20
are all DW8's turbocharged?

I wish! No, they're all NA
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Re: 1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot d

Post by MikeT » 08 Jan 2018, 15:44

kenbw2 wrote:
08 Jan 2018, 15:32
MikeT wrote:
08 Jan 2018, 15:20
are all DW8's turbocharged?

I wish! No, they're all NA


Indeed, I just looked it up - not until HDI's did they add a turbo.
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kenbw2
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1994 Peugeot 106 1.5D: seen better days
1996 Peugeot 106 1.5D: cremated
x 8

Re: 1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot d

Post by kenbw2 » 08 Jan 2018, 15:48

As I understand it the DW8 is a bodged together XUD9 block and TUD5 head to get them through emissions regs before the HDis came in/became affordable.

It's the last of PSA's mechanically driven engines, although I'd rather have my turbocharged XUD9 back :(
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Re: 1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot d

Post by MikeT » 08 Jan 2018, 16:02

kenbw2 wrote:
08 Jan 2018, 15:48
As I understand it the DW8 is a bodged together XUD9 block and TUD5 head to get them through emissions regs before the HDis came in/became affordable.

It's the last of PSA's mechanically driven engines, although I'd rather have my turbocharged XUD9 back :(


Maybe it's not a good idea to tweak this engine for power, having read "The EW/DW uses many parts from the XU, most notably the crankshaft, but is built with lighter materials"
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kenbw2
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1999 Citroen Dispatch 1.9D DW8: daily driver
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1994 Peugeot 106 1.5D: seen better days
1996 Peugeot 106 1.5D: cremated
x 8

Re: 1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot d

Post by kenbw2 » 08 Jan 2018, 16:19

MikeT wrote:
08 Jan 2018, 16:02
Maybe it's not a good idea to tweak this engine for power, having read "The EW/DW uses many parts from the XU, most notably the crankshaft, but is built with lighter materials"


I'd be interested to see if that's also true of the DW8. I think the DW8 is a bit different from the other DWs ("The DW8 is for all intents and purposes an evolution of the XUD9"). It could be true of that too, but I'm not sure.

In any case, I doubt any tinkering I could do to the pump would make enough of a difference to put that much strain on the crankshaft/other parts.
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Re: 1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot d

Post by MikeT » 08 Jan 2018, 18:34

I referenced wiki, maybe others would know more about your engine's strengths and tuning options. I don't suppose an XUD9T transplant is an option for you?
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kenbw2
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Posts: 141
Joined: 23 Dec 2014, 01:24
Location: Bradford
My Cars: -
1999 Citroen Dispatch 1.9D DW8: daily driver
1997 Peugeot 806 1.9TD: backup vehicle
1996 Citroen Synergie 1.9TD: donor car
1994 Peugeot 106 1.5D: seen better days
1996 Peugeot 106 1.5D: cremated
x 8

Re: 1990s Bosch diesel pumps allowed for increasing fuelling. What's the difference between that and putting your foot d

Post by kenbw2 » 08 Jan 2018, 18:40

MikeT wrote:
08 Jan 2018, 18:34
I don't suppose an XUD9T transplant is an option for you?


Ugh, I went down that road when I was looking to get a Bosch pump fitted but couldn't get my hands on any DW8 Bosch pumps (before I learned that XUD9 pumps can be fittd to DW8s).

The garage was willing to give it a go but couldn't give any ideas of cost or guarantees of success. I know one issue will be that engine mountings are probably different - I know that's definitely true of an HDi-to-XUD conversion.

It's probably doable, especially by someone that specialises in PSAs, but I wasn't willing to take the gamble.
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