Tuning an XUD9TE for max MPG

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Tuning an XUD9TE for max MPG

Post by kenbw2 » 15 Mar 2019, 00:13

I've seen lots of instructions for how to tune an XUD9 Bosch pump for performance by screwing in the max fuel screw.

To what extent can I make adjustments to improve MPG? Is it worth backing it off some, or is it going to be perfect where it is?

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Re: Tuning an XUD9TE for max MPG

Post by xantia_v6 » 15 Mar 2019, 02:20

You would achieve the same thing by putting a block of wood under the accelerator pedal. Turning back the max fuel screw only adjusts how much fuel is injected at maximum throttle.

I doubt that there is much you can do to improve the efficiency of those engines.

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Re: Tuning an XUD9TE for max MPG

Post by Paul-R » 15 Mar 2019, 12:27

Is an XUD9 or XUD9TE? If it's a turbo engine you could increase the maximum boost pressure and fit a large intercooler. Apart from that I can't think of anything engine specific.