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JM_S2

Setting up new tune

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Hi

When i got my car it was tuned by local firm and after some digging of it i' not at all satisfied with it.  Scaling is crap, basically from 20-27 in the whole table(MGP) and according to how it behaves injector setup isn't right either.  Hot start issues (goes very lean when IAT rises).  Injectors were totally wrong in 300hv engine (bosch EV14 1200cc).  First we did a remap and got it better but probably because of those injectors it is hard to get wider scale in fuel table.  Fuel economy is quite poor too...

I have now changed injectors to EV14 550cc and because there really isn't much to spare from the previous tunes i have decided to do it all over again.  I tried to scale down master fuel but even when i got it sorted my car started to run very rich.  With 1200cc injectors MF was 14ms and according to my math it should have been in right area with 550cc injectors and 31ms.  It wasn't and car ran idle at 0,7AFR.  So with tune like this it is probably better to start it all over.

Basic setup is 3.0L 4-cyl supercharged engine with those Bosch EV14 550cc injectors and COP ignition.  My plan is to drive with ethanol in near future and i'm also planning to install continental ethanol sensor. Plan is to get it right first with gas, then with ethanol and in the end i'll have multi fuel sensor wired.  If i understood right it is better to do it in modelled mode.  The problem is that i'm missing some information of injectors.   I do have dead time tables but that's about it.  I don't have injector setup menu where to pick up right injectors (is that firmware related?).  Does somebody have basic information of my injectors which i could use in my new tune? Injectors are standard model of EV14 550cc with delphi connector.  That sheet doesn't give much information to begin with.

http://www.bosch-motorsport.com/media/catalog_resources/Injection_Valve_EV_14_Datasheet_51_en_2775993867pdf.pdf

Tuning itself isn't a problem, it's the setup...

 

 

Edited by JM_S2

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Yes, definitely use modeled mode if you plan to go flex fuel later.

For relatively small (550cc) injectors, deadtime data is really all you need.  Your pulsewidths at idle will be big enough that the short PW adder table wont have any effect so just leave that at zero.

I suspect however if you are planning on E85 later, those might be a bit on the small side?

Edited by Adamw
spelling

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Ok. Thanks alot! Yes, i know those injectors are a bit on the limit with E85.  Especially when you get to change the ignition mapping.  We'll see how it goes with duty cycle.  I'm not planning to go beyond 350hp and if they appear to be too small then i just have to buy new ones. 

 

Edited by JM_S2

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True that.  Might be possible to play a bit with fuel pressure but on the other hand set of 750cc EV14 injectors doesn't cost a fortune.  Today we changed fuelling mode to modelled and made some tuning.  It's far from ready but very well driveable.   Hot start problems are gone and car works better than ever.  The big question is the numbers in the table.  It looks quite strange.  I understand the units but the numbers don't make much sense to me.  Are those percentages some kind of corrections to estimated fuel calculations?  This would explain it but if that is not the case there has to be something very badly wrong...  Could somebody have eye on my PCLR file?

944multi.pclr

Edited by JM_S2

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I think you need to have a look at your fuel density parameters (and also after that things that will effect - ie the fuel table). Also charge cooling coefficient and charge temp approx table don't look right.

(edit - not to say there aren't other things, it just looks like fuel density is out by around a decimal point which would stuff things up. The fuel table is supposed to represent VE of the engine)

Edited by CamB

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Just in case you didnt know, you can click on most settings and the help file will automatically jump to the correct page and either give some suggested values or explain what the setting does.  An example below after I clicked on the fuel density setting.  This should give you most of the basic values needed.  Same with the charge temp table, just copy the example in the help file.

In modeled mode you should also turn off the IAT fuel correction, it is still enabled in your map.

wN6geSq.png

Edited by Adamw
typo

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Ok. I already altered fuel mass value and now numbers in the fuel table changed a lot.    In the Left upper corner (idle) values are now around 78-80.  Have to disable that IAT correction too.  It is very irritating to start tuning over old map which apparently has more false than right values in the setup fields.  

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Went through all the menus/setting which i thought are necessary for acceptable result.  IAT is now disabled but it caused problems immediately.  In Porsche 944 intercooler is in nasty place where it gets heat soak when standing on idle.  IAT temperatures tend to raise around 45C and even over it.  It comes down as soon as you drive a bit faster but on the idle and crawling speeds it is a problem. Earlier i fixed that with IAT correction but now i don't know how to archive same result.  Maybe by tweakng idle solenoid opening values.

 

Then about tuning.  Usually i have done it so that i disable everything which might interfere fuel table building.  Acceleration enrichment, lambda correction ect.  Then i've been driving around and my friend has done the numbers.  High power areas we have done with auto tune and then tweaked it a bit to get it nice and smooth.  End result has been nice fuel table where afr-ratios are all in place even without labda correction.  In the end i'll just switch those features back on.  Is this ok way of tuning modelled system or should it be done differently?  New pclr file is attached but only idle cells are on the right area and their values are still too high.

 

Edit:

I already noticed that my IAT sensor might not be in best place.  It is quite close to throttle body but on the wrong side of it. Maybe i have to fix that first...

944multi_corrected.pclr

Edited by JM_S2

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I don't think having your charge temp table at 100% is helping. There is quite a detailed discussion in the help file on how to set it up. I think it is completely ignoring the IAT with it 100% (and therefore effectively assuming IAT is the same as ECT).

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JM_S2, I also notice you are on quite old firmware.  I suggest you download the latest G4+ software and do a firmware update.  Then use only the G4+ software.  There have been many improvements and bug fixes since 5.4.1 that you are using.

As Cam says, its really just your charge temp table that needs fixing now.

You also need to correct the fuel density temp coeff - that wont make a difference now but if it is left wrong and you add a flex fuel sensor later then it will drastically effect your existing tune.

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Now it starts to look good.  Lowest values are still quite high but on the other hand 0,75L cylinder needs more fuel than smaller bores.  I was thinking about location of IAT sensor.  Woud it be better to weld a bung in venturi pipe or in throttle body?  It would be quite easy to bore and tap threads in TB.  In the other end of the plenum i have all the vacuum connectors and there is still one slot free which could be  also used. Picture engine bay below

Engine bay

Free slot

 

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