Vauxhall 20xe map/info needed

Post maps up for others to get them going in the right direction. DISCLAIMER: USE AT YOUR OWN RISK. CONFIRM VALUES!
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madmax53
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ECU Model: S40 Pro
Distributor: QED
Location: Guernsey

Vauxhall 20xe map/info needed

Post by madmax53 »

Hi Guys

I've just re-built the engine this year and is running the QED motorsport kit Q450V camshafts, forged pistons, race valve springs, race rod bolts, jenvey throttle bodies, Bosch 803 race Injectors (381cc @ 3bar), DTA s40 pro ecu.
All fitted to my Dallara f394.

Basically when I started the engine for the first time, with the map that was installed from QED it wouldn't run, called them and it seemed the wrong map was uploaded for my setup, they sent me some maps but the one I really need had been over written by someone :roll: .
Anyway I have a map installed but this one does over fuel on low revs but has a good power distribution in the higher rev range, engine is very bogey at low speeds, so after some info / maps for this setup.

I know I really need to get it on a rolling road but its expensive to get off Guernsey and get to the main land, so this probably wont happen till next year.

If anyone could help It would be appreciated

Cheers Simon
katana
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Re: Vauxhall 20xe map/info needed

Post by katana »

Presume you are using Ballast resistors in the injector feeds? And you are aware they will be running group fire ie. 1&4 and 2&3 so it is liable to be receiving twice as much fuel as the map implies - at higher rpm this won't be so noticeable ......... you'll just use more fuel!
Try scaling all the sub 4500 rpm and 50% TPS map numbers down by say 40% and try that to see if any improvement? BTW 803's aren't race injectors - just regular ones as fitted to Porsche 944's etc.
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madmax53
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Re: Vauxhall 20xe map/info needed

Post by madmax53 »

As far as im aware the injectors are high impedance so no need for the resistors,
looking at the map im running if I was to lower it by 40% it would be the same as the original map that was installed and it wouldn't run.

would lowering it by 10% be a safe place to start?
Also can the same be done for the start up map?

Cheers Simon
katana
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Re: Vauxhall 20xe map/info needed

Post by katana »

Have to disagree re the impedance - see here .... http://www.clarks-garage.com/shop-manual/fuel-12.htm
When you say it wouldn't run - does that mean it wouldn't run at all, wouldn't start or wouldn't continue to run even if badly? It might imply something else was awry with the map set-up. I'd still go -40% - but 40% of the difference between the original and the 'rich' one now? Start up maps are best left alone until the general running and the hot starting are pretty much spot on - its a PITA but usually the best method. Do you use a wideband and logging? Without you don't really know what is going on with the mixture - may not be 'too' rich - could be a misfire just ejecting un-burnt fuel?
MarcoV6T
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Re: Vauxhall 20xe map/info needed

Post by MarcoV6T »

katana wrote:Presume you are using Ballast resistors in the injector feeds? And you are aware they will be running group fire ie. 1&4 and 2&3 so it is liable to be receiving twice as much fuel as the map implies - at higher rpm this won't be so noticeable ......... you'll just use more fuel!...
Not sure where you heard that, but batch fire will not inject twice the amount of fuel (in respect to the map); if it's firing one group after the other each revolution, then it will inject the full injection time(+ dead time) for each group, if it fires all injectors at the same time, then it will inject only half the injection time(+ dead time) each revolution.

But, if the dead time is way off, then the 'true' injection time will be off also, when all injectors fire half the injection time each revolution, because it will also add twice the dead time(that's also DTA's way to 'calculate' the injectors dead time, switching between batch fire and sequential).

madmax53, how do you know the mixture is too rich? The only way to know for sure is to measure it, even a 'known good map' could be off for your engine, due to tolerances and slightly different hardware/configuration.

Also, always give what the engine wants/likes, if it runs better a little richer/leaner, then go for it.

But first, as katana mentioned, get a wideband lambda sensor first, you need to have a starting point/reference somewhere.
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madmax53
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Re: Vauxhall 20xe map/info needed

Post by madmax53 »

Basically on the original map it would just about idle but as soon as you touched the throttle it would die,
Start up with the current map it is very rich as in smell and poufs of black smoke when revved + the plugs are sooty.
I tend to lunch at around 4000-4500 rpm any lower its very boggy and takes what feels like ages to get up to speed and the same with slow corners.
I have a lambda fitted but have no way of data logging when under load,(should of gone for the S60 :roll: )

Sorry about sounding vague, but its all new to me and to be really honest I really don't know what im doing hence looking for advice, but im trying to learn as much as my little brain can take ;) ,

Cheers Simon
katana
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Re: Vauxhall 20xe map/info needed

Post by katana »

MarcoV6T wrote:Not sure where you heard that, but batch fire will not inject twice the amount of fuel (in respect to the map); if it's firing one group after the other each revolution, then it will inject the full injection time(+ dead time) for each group, if it fires all injectors at the same time, then it will inject only half the injection time(+ dead time) each revolution.
See that's where i'm spoilt - i've only ever done installs featuring a sync sensor so the map numbers are reflecting a single injection event per cylinder per cycle - a map set up for batch I would imagine will be 50% of the above numbers due to two inj. events per cycle? Or are the map numbers the same for either batch fire or sequential and the ECU determines a 50% injection time for the former?

Its all a learning experience I suppose!
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madmax53
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Re: Vauxhall 20xe map/info needed

Post by madmax53 »

screen shot of the lambda history attached :?
Attachments
DSC_0004.JPG
DSC_0003.JPG
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