power of diesels

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renagade
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power of diesels

Post by renagade » 18 Jul 2017, 17:13

Why do Citroen have two power bands for the 1.6 hdi. My c5 x7 e-hdi has the 1.6 e-hdi that puts out 110 bhp . but I notice they do a 1.6 hdi that puts out 115bhp and some even more power out of the 1.6 hdi.

I have noticed a big difference in take off with the AC switched on and with it switched off. On my 2009 c5 x7 with the 2lt hdi engine there was not a lot of difference .
How can I squeeze a little bit more bhp out of my 1.6 e-hdi ??????

onix45
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Re: power of diesels

Post by onix45 » 20 Jul 2017, 11:30

Regarding your last question: the only way to get more power out of the same diesel engine without changing any parts is remapping. I had mine remapped, had a +40Nm increase and a total of 135 bhp, but the egs box could not take it, so now i have decreased it to around +15Nm and around 130 bhp, and a wider power band. Its not as fun as it was with the +40Nm tune, but it is still has a noticeable pull increase from stock and at least the egs box is not acting up.
However, if you do decide to get it remapped be sure to go to a company that knows Citroens and knows how much an egs gearbox can take.

renagade
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Re: power of diesels

Post by renagade » 21 Jul 2017, 10:12

Hi onix45
What do you mean the egs would not take a big hike in power. What happened???? Has you know I have just spent 2k on my egs that packed up on me a couple of weeks ago.

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GiveMeABreak
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Re: power of diesels

Post by GiveMeABreak » 21 Jul 2017, 12:00

The system software that controls the actuators is calibrated to work with certain power levels / torque / ratios, so changing these will cause problems with the system - basically put.

onix45
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Re: power of diesels

Post by onix45 » 21 Jul 2017, 12:22

GiveMeABreak wrote:
21 Jul 2017, 12:00
The system software that controls the actuators is calibrated to work with certain power levels / torque / ratios, so changing these will cause problems with the system - basically put.

^This

Basically, the gearbox would "slip" after a gear change if i was pushing it hard enough (after a gear change the revs would stay in place as the speed increased). It was explained to me by a highly regarded local French car chip tuning shop, that this was in fact not a mechanical problem, but rather a software one. The egs software is calibrated for stock power, so with the power increased it purposely let the clutch slip, until the engine speed matched the car speed in a certain gear. This was probably made to increase riding comfort, but with increased power the egs software doesn't know whats going on.
But after tuning it down to around +15Nm, i can feel that the problem is gone. Since the torque curve is much more horizontal now, than it was when stock, i still have around 130 BHP.

You can find more info about this problem i am explaining if you check my thread history.


Edit: also, i do believe that the egs gearbox could take up to about +30Nm torque increase, but you would be sacrificing its longevity. How much? Who know, but the fact is that the egs box is not tuning friendly. If you do intend on keeping this car i would get a tune that would add maybe 10-15Nm but more importantly - widen the peak torque band as much as possible. My peak torque at stock was around 2300 rpm and then started going down as the revs increased. Right now the peak is basically at the same spot but there is very little drop until around 4000 rpm, and i can really feel it.

renagade
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Re: power of diesels

Post by renagade » 23 Jul 2017, 10:48

In that case I will leave well alone having just spent all that money to get it repaired.

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GiveMeABreak
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Re: power of diesels

Post by GiveMeABreak » 23 Jul 2017, 11:31

I think that is good advice from yourself. Next time, if there is a next time ( :-D ) manual or fully automatic would be my advice :wink:

renagade
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Re: power of diesels

Post by renagade » 24 Jul 2017, 09:25

Your not wrong
These piloted gear box's ,?what was Citroen thinking of. i had a DS Pallas with the semi auto box which for the day worked ok.

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GiveMeABreak
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Re: power of diesels

Post by GiveMeABreak » 24 Jul 2017, 10:06

Ditto with my 'C-Matic' semi auto CX Prestige. Loved it.

renagade
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Re: power of diesels

Post by renagade » 24 Aug 2017, 10:11

I remember on my cx c-matic , if the box was not working as it should you had to adjust the "points" on top of the gear box and all would be fine again.