Mapping - Who\'s tried it themselves?

[L18M]

i have pretty much 0% understanding on mapping but just wondering, when you map a car. how do u map it for say when you doing 100+ mph?
ie, is the map based on the rev range unloaded and loaded or does the speed play a factor with the map?

sorry if its a really dumb question!
just thinking if u map on the road you cant really take the car to 130+mph to map it lol

[Prof]

i have pretty much 0% understanding on mapping but just wondering, when you map a car. how do u map it for say when you doing 100+ mph?
ie, is the map based on the rev range unloaded and loaded or does the speed play a factor with the map?
 
sorry if its a really dumb question!
just thinking if u map on the road you cant really take the car to 130+mph to map it lol

It\'s not a dumb question.
 
Clearly the top parts of the rev range and higher gears really need to be done on the dyno - where you can do any speed you like.
 
You tend to hit higher boost in higher gears anyway, as there is more load on the car from drag and wind resistance.  However, you can get a fairly good tune in 3rd gear pulls up steep hills and then tweak it on a dyno later.  As long as you tune conservatively - so keep it on the rich side of safe, and check your boost controller for spikes by checking peak boost reached after any \'ragging it\' runs.
 
The other thing a dyno will let you do is sit at given RPM or boost for as long as you want - not possible to do that on the road.

[Rub87]

Anyone already tried to remap the stock ecu.? maybe if we gather knowledge we can find the correct maps/value in the bin and then the need for a piggyback or standalone is gone..
 
I\'ve readout a tuned ROM, and asked Prof for a original file, so I can spot the differences..
 
the main problem is I do not have experience with these 8 bit FC ecu\'s, so I do not know the factors used in these maps and the axis locations, as I usally map 16 bit Bosch diesel ecu\'s for VAG TDI\'s (msa15, edc15 & edc16), and I have little experience with petrol ecu\'s, altough I know the principles of the working of these engines quite well..
 

 
Here you see some of the changes made in the maps..

[ianelvar]

That\'s definately worth a go I reckon. I\'ve got a spare jap spec ECU I can pull apart, so I\'ll have a look. I just found this from a quick google search: http://www.16paws.com/ECU/index.html
I might get in contact with the guy to see how he\'s getting on.

[Rub87]

I got also a N374 RE-Amemiya C-type ecu, when you plug it in car with oem boost control system it settles nice at .8 bar midrange and tapering off towards redline, this is a feature the other remapped ecu I have doesn\'t do, so with those you need to run a separate boostcontroller..
 
Altough it seems the RE-Ameiya ecu is the superior ecu, it is much more responsive off boost, and seems to have more torque with equal boost..
 
Too bad the eprom is epoxied on the board :/

[ianelvar]

Interesting. Epoxied chip doesn\'t have to be a problem. I do a lot of work with surface mount EEPROM where I just mount a chip clip on top and read it while in the board. I\'ll have a quick look inside my spare and see what I can come up with, then maybe we can start comparing ROM images

[Rub87]

I tried to read it thru the backside of the board, so I slided a socket on there and that in the eprom reader but the file doesn\'t seemed like correct at all :/ can it be that it\'s corrupt because of reading it on the board? a bad connection is also a ....bility as it used to be covered in epoxy too on that side

[Prof]

I wonder if it\'s possible to make a daughter board using a surface mount pic that would replace the processor and ROM, as long it has the same inputs/outputs to the logic board, you can then provide facilities like USB connection or serial port direct to the board, so you\'ve got programmability.  I presume some of the ROM space is just tables, and some is code - might have another look at my spare ECU and see what\'s possible to achieve.
 
The other posibility is to replace the digital board outright - as all the ECU sockets are on the analog board  This would make the choice for processors quite wide.
 
I like what that guy\'s done with the ECU tester - that was something else :Thumbs-up  
 
Give the A to D chip is 16 channels but 8 bit (256 values), the tables can not be bigger than 256 cells.  Quite likely they are smaller.
 
Just out of interest Ruben, what was that software that displays the mapping tables.  I presume were are looking at timing, but what\'s the other table ?

[stocky]

i cant see the web page that you linked to prof
it just says ip banned and when i click contact administrator it brings up a program that i cant use does anyone have the email address for the admin of the site??

[Prof]

i cant see the web page that you linked to prof
it just says ip banned and when i click contact administrator it brings up a program that i cant use does anyone have the email address for the admin of the site??

The links on the FC3S site ?

[Rub87]

I wonder if it\'s possible to make a daughter board using a surface mount pic that would replace the processor and ROM, as long it has the same inputs/outputs to the logic board, you can then provide facilities like USB connection or serial port direct to the board, so you\'ve got programmability. I presume some of the ROM space is just tables, and some is code - might have another look at my spare ECU and see what\'s possible to achieve.
 
The other posibility is to replace the digital board outright - as all the ECU sockets are on the analog board This would make the choice for processors quite wide.
 
I like what that guy\'s done with the ECU tester - that was something else :Thumbs-up
 
Give the A to D chip is 16 channels but 8 bit (256 values), the tables can not be bigger than 256 cells. Quite likely they are smaller.
 
Just out of interest Ruben, what was that software that displays the mapping tables. I presume were are looking at timing, but what\'s the other table ?

I think those 2 upper ones are timing, trailing/leading, and the others are probaly fueling related.., problem are the factors/offset with these 8 bit ecu\'s, this is much less of a problem with 16bit ecu\'s and when you have to possibility to log every in/output
 
I use winols to work with the bin\'s..
 
a good way to learn things is when you have a emulator, so you can view in realtime the places where the data is being read, like for instance you can do with motec ecu\'s and probaly most of the standalone\'s, and have the possibility to change data in realtime
 
anyone has a 27(c)256. emulator.. prof..?

[lee mills]

Just starting to have a look round my current map using datalogit with pfc. Im completely new to this so bare with me. the pfc uses a 20x20 screen the horizontal numbers being rpm which is fine got to grips with that. What im trying to understand is what values the vertical numbers represent.I presume these values will change dependant on how much boost you are running but for example if you were running 1 bar what would these values represent.

[Prof]

I think those 2 upper ones are timing, trailing/leading, and the others are probaly fueling related.., problem are the factors/offset with these 8 bit ecu\'s, this is much less of a problem with 16bit ecu\'s and when you have to possibility to log every in/output
 
I use winols to work with the bin\'s..
 
a good way to learn things is when you have a emulator, so you can view in realtime the places where the data is being read, like for instance you can do with motec ecu\'s and probaly most of the standalone\'s, and have the possibility to change data in realtime
 
anyone has a 27(c)256. emulator.. prof..?

I built the 27256 Eprom emulator in Elektor -  but the board is quite large and it\'s loaded via rs232 - I am looking to find a usb based eprom emulator that has a footprint not much larger than the eprom chip, that would be the ideal tool for this sort of job.
 
I\'m interested in any feedback from folk who have built and or used either the Megasquirt or VEMS ECU\'s on a rotary engine.  In particular any issues that you had.

[ianelvar]

Just starting to have a look round my current map using datalogit with pfc. Im completely new to this so bare with me. the pfc uses a 20x20 screen the horizontal numbers being rpm which is fine got to grips with that. What im trying to understand is what values the vertical numbers represent.I presume these values will change dependant on how much boost you are running but for example if you were running 1 bar what would these values represent.

Have a quick look here bud, page 14 deals with fueling. They represent manifold pressure, and via some clever calculation, air flow. The post I made a couple of weeks back on fueling should give you a bit more info, but I think the apexi has the axis swapped compared to the system I use.

http://www.mazdarotaryclub.com/general/apeximanuals/RX7Tuning.pdf

[ianelvar]

I built the 27256 Eprom emulator in Elektor -  but the board is quite large and it\'s loaded via rs232 - I am looking to find a usb based eprom emulator that has a footprint not much larger than the eprom chip, that would be the ideal tool for this sort of job.
 
I\'m interested in any feedback from folk who have built and or used either the Megasquirt or VEMS ECU\'s on a rotary engine.  In particular any issues that you had.

I\'ve found a few schematics for emulators. None of them look hard to build, and all work off a parallel port.
I\'ve also found a few commercial products, but they\'re expensive and no smaller than the DIY versions, and all have a ribbon cable from the box to the \'chip\' connector. I can make up one of the circuits given time though.
If you want it really small it\'d have to be SMT, and that\'s no so easy though.