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Overshooting boost target&limit ESL

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Old 11 February 2017, 01:25 PM
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ossett2k2
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Default Overshooting boost target&limit ESL

Car is a v3 running ESL and Mafless.
I'm overshooting my target boost by a lot,currently it's set to 1.25bar and as i'm mafless the boost limit table is set to 1.40bar in the far column(1.012 baro in the look-up table)
I thought with it set like this then my boost would cut at 1.40bar but i'm hitting the boost ceiling of 1.72bar.

One thing i have noticed is on live data when logging is that the barometric pressure(LUT) window shows 1.012 as it should but barometric pressure(Bar) window shows 2.024 and it's a red figure.

I know i can adjust my WGDC to get my boost closer to my target but i don't know why i'm overshooting my boost limit by such a long way ?

Cheers
Rich

Last edited by ossett2k2; 12 February 2017 at 08:37 PM.
Old 12 February 2017, 08:48 PM
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I've been looking over some settings and have found a difference in the map sensor perameters from what the stock 6s map that came with the ESL ecu and what the ESL manual says.
Boost gradient: 643
Boost offset:414
Baro gradient:54857
Baro offset:542
These are all the same in manual and what I have.
The difference/conflicting info is:
Baro SSM: 20572(ECU) and 12380(what the manual says)
Baro SSM offset:52(same on both)

I will try putting in the figure that it says in the manual to see if this is where my problem is,but if anyone with a 97/98 running ESL could check their baro SSM gradient is then I'd be most greatful

Just not sure if either the info in the manual is wrong,I have got the wrong prameters or if this figure would even effect boost cut?

Last edited by ossett2k2; 12 February 2017 at 08:49 PM.
Old 19 February 2017, 01:45 PM
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Jaysz
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All mine are same as the manual
Does boost target even do much my map that had done target and boost not even near same I just moved target closer to actual Boost
Sure want duty set to run boost need so ecu not trying correct boost so much
Old 19 February 2017, 02:04 PM
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Thanks for the reply Jay,I've changed everything as per manual now but not had chance to really test it out,I don't like hitting 1.7+bar too often at the moment.
Looking at my boost gauge I'm still overshooting tho as I'm still hitting over 1.5bar before I back off the throttle.
I know it's the WG duty which controls boost rather than the target so I will keep lowering duty until i can get it where I want.
I'm just struggling to know why my set boost limit is not working to boost cut and is overshooting by so much? I thought it was there for safety measures?
Old 19 February 2017, 02:59 PM
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Just tried mine with two different limits seems to limit 0.2 bar higher than what set at but not a smooth cut
just use duty on mine
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Old 19 February 2017, 03:09 PM
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Nice one.
I will have a tweak of the duty and see how I get on

Last edited by ossett2k2; 19 February 2017 at 03:11 PM. Reason: Misread post
Old 19 February 2017, 03:14 PM
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Have you changed the perameter in the baro SSM gradient to test Jay or is this how you have it? The figure in the manual says 12380 in that column.
Old 19 February 2017, 03:30 PM
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Just noticed one of the settings is different to manual was changed by mapper
Pic is how was set up and not changed any of those
Old 19 February 2017, 04:27 PM
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Ok thanks again for the advice,I have a 3 port bcs to fit which I'll probably do on Friday so I will have to redo the WG duty tables,the 3 port should also give better control.




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