Author Topic: what is "map corr table"  (Read 11900 times)

Offline Denmark

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what is "map corr table"
« on: February 17, 2010, 01:28:59 am »
I have been converting a file from 1.1.44 to 1.1.64 and all the tables is going nuts, i have plugged in the numbers in all the tables from the old firmware, but there is a MAP Corr table 8x8 table, that i dont know what is , and i cant find anything about it.

What does it do , and do someone have a startmap, that i can use, is there any other problems that i need to know before trying it on the car?
or is it better to try a newer firmware?

Thanks,
Skassa
working on the boxer

Offline dnb

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Re: what is "map corr table"
« Reply #1 on: February 17, 2010, 01:36:51 am »
I don't think you need it for normal speed-density operation.  As far as  I understand things, it's for alphaN on boosted engines.

On my TVR it's set to 100% for the whole table and this seems to work.

Offline Denmark

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Re: what is "map corr table"
« Reply #2 on: February 17, 2010, 01:57:50 am »
Okay thanks, so it's not needed,

Strange that i just read the other Day that when upgrading the firmware it was just a matter of upæoading the new firmware and then just upload the config, but almost any setting that could be wrong is wrong in my setup, but i Think that most is like it's surposed to now, i Will give it ago in the car tomorrow :)


Thanks
Skassa
working on the boxer

Offline MWfire

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Re: what is "map corr table"
« Reply #3 on: February 17, 2010, 02:51:54 am »
Yes, only needed for alfha/n(ITB) with turbo.

Offline gunni

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Re: what is "map corr table"
« Reply #4 on: February 17, 2010, 03:45:50 am »
I´ll probably be using this on a S50B32 BMW engine that is getting a turbo soon and vems.
So I´ll be able to report back with feedback.

Offline MWfire

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Re: what is "map corr table"
« Reply #5 on: February 17, 2010, 03:54:02 am »
I´ll probably be using this on a S50B32 BMW engine that is getting a turbo soon and vems.
So I´ll be able to report back with feedback.
ok, but soon will be new firmware, with better ign tables for that setup(ITB+turbo).

Offline gunni

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Re: what is "map corr table"
« Reply #6 on: February 17, 2010, 04:30:40 am »
How so?


Offline GintsK

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Re: what is "map corr table"
« Reply #7 on: February 19, 2010, 12:04:40 am »
Does anyone have experience with AlhaN *MAP tuning.

What is right steps? to tune with no boost as n/a first? And then try to find Mapcorr table shape with boost applied more and more?

I have to tune such car in near future. Is it completely impossible to use pure Speed-density?

Gints

Offline MWfire

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Re: what is "map corr table"
« Reply #8 on: February 19, 2010, 12:58:48 am »
Does anyone have experience with AlhaN *MAP tuning.

What is right steps? to tune with no boost as n/a first? And then try to find Mapcorr table shape with boost applied more and more?

I have to tune such car in near future. Is it completely impossible to use pure Speed-density?

Gints

Ve, and that map table is easy to tune. That is only for having less lambda at boost. So if you set VE table to have lambda 0.86 at wot without turbo, and you want to have lambda 0.78 at 2bar of boost, then you put  110 in map corr table for 300kPa(110=(0.86/0.78)*100)).
And for ignitio you need to use kPa for Y axis. But if you have map sensor before throttle, in vacum you will have constant ignition what is bad. New firmware will solve that problem.

And you can go with speeddensty but you will need to connect 4 vacuums to one.

Offline GintsK

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Re: what is "map corr table"
« Reply #9 on: February 19, 2010, 01:49:21 am »
Quote
Ve, and that map table is easy to tune. That is only for having less lambda at boost. So if you set VE table to have lambda 0.86 at wot without turbo, and you want to have lambda 0.78 at 2bar of boost, then you put  110 in map corr table for 300kPa(110=(0.86/0.78)*100)).
And it still works in closed loop with lambda target 0.78?

How accurate is this strategy? It use just multiplying with absolute pressure when above 100Kpa. I suppose engine did not get air in exact same amount as simple multiplying result. Some difference to decreasing direction expected due to rising restrictions and turbo back-pressure.
I supposed this effect can be described with Mapcorr map. But now it becomes more unclear to me.

Quote
And for ignitio you need to use kPa for Y axis. But if you have map sensor before throttle, in vacum you will have constant ignition what is bad. New firmware will solve that problem.

And you can go with speeddensty but you will need to connect 4 vacuums to one.
Engine use ITBs form M-power inline-6. Volumes after throttles are joined with rail similar as used for injectors. OE use it for idle bypass. I have plan to connect MAP sensor there.

Offline gunni

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Re: what is "map corr table"
« Reply #10 on: February 21, 2010, 09:36:10 pm »
I need to know that if I go above 100kpa at any other TPS value less then the maximum TPS% in the Alpha-n table that the value in that TPS value is not used rather the values in the maximum alpha-n scale. Otherwise this could lead to problems when boost comes on sooner then expected.


Offline GintsK

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Re: what is "map corr table"
« Reply #11 on: February 21, 2010, 10:37:53 pm »
Not sure: at mid range of rpm you can expect boost even at 25-30% throttle.

If Alpha-N table is for example 75% of maximum value at given rpm, it means throttles create restriction to flow. If some turbo pressure comes we can expect even harder restriction. At this point using upper value from fuel table mens over-rich. Or I am wrong?

Offline gunni

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Re: what is "map corr table"
« Reply #12 on: February 22, 2010, 12:05:37 am »
It would be wise to scale the TPS range to that at no point are you able to make boost at less then the highest range
But that´s a range of possibly 30-50% depending on the engine .

I know alot of engines start making boost at 30%. So it would be scaled 0-30% for them.
I just need to know how the ecu thinks.