MartinFranck/Projektstate (2006-03-16 04:43:08)

Ignition on a Mini-Turbo (No injectors)

Maximum planned boost is 0,8bar = 11,76PSI = 80Kpa, so max MAP reading will be 180KPa.

Planned rev limit is 7500 RPM


Project state

DONE

TODO


Sensors - already mounted:


Idle air


Trigger

The primary trigger input channel must be set up with the relevant jumper to VR-type input (so LM1815 is used).

I have uploaded new and better pictures of the board, they can be seen here: MartinFranck\Pictures

The other option would be HALL type: therefore this is only done before shipping when the user declares (eg. on project wiki page, or order note) that he needs VR type.


Ignition

Wasted spark: 2 channels for 4 cylinders.

I can´t figur it out with the starting dwell, I have looked on DummyIgnition. But if I start carefully with 2.5 msec, is´nt that okay too start with?

2.5 msec

x=2500/64 x=39 Hex(39)=27

so:

ign_dwelll4=27 # hex(27)=dec (39) ; 39 * 64 us = 2500 us dwell

Spark problems

I have tried to fire up the engine, but there isn’t any spark.

The English DTA controller has starting settings that controls how many RPM that the engine needs too take before the controller will allows any sparks.

No such parameter for GenBoard, the max position after the trigger is limited to 131msec (this means min 40..120 RPM depending on trigger and ignition advance setting).

It seems that some steps were skipped before cranking. Namely the mdn.. tests.

Very handy, because it allows testing spark infrastructure without cranking.

Good luck !


Pin connections and h[2] table

Pin connections can be seen here MartinFranck/Wiring

Some very important settings like

will depend on

  • cyl1 and cyl4 or
  • cyl2 and cyl3

This is of critical importance to document precisely.

... coming up


config.txt

http://www.vems.hu/files/MartinFranck/MFConfig.txt


Ignition advance table

described in the n[ ] table (8x8 or 16x8)

Obviously, lower ignition advance is needed at highy MAP (> 100 kPa is possible because of the turbo). This means n[7] will hold lower values than n[0]

The following kpa and rpm ranges could be used (or other can be good too):

r[0] = 07 ... <5 RPM values of your choice> ... 40 48 (Also which format is the numbers)

k[0] = 18 40 64 90 B0 ... <2 values of your choice> .. FF (18 40 64 what is these numbers in e.g Hex ?)


You can take a look at my table file, it has plenty of hints should be enough to get you going:

http://vems.hu/files/DaveBrul/tables.txt - DB


You don't need too many bins initially, it just increases tuning time. For ignition during the 2nd phase (fine-tuning) you might find it a good idea to insert an rpm or kpa bin somewhere, so keep one "free" during the first round (spread your useful range across 7 bins and place the 8th somewhat beyond).


Question

Q: Have I understood it correctly, that if I want the ignition advance too be 30 deg, that i then should multiplicat with 2, so that I should write 60 deg = 3C (Is this correct)

A: That is incorrect, the timing unit of the ignition map (n) and ign_crank_advance is 0.25 degree. Therefore, 30 degrees = 30 x 4 = 120 = 0x78.

Q: I have tried to converts the config.txt to .mtt, by writhing make mtt in command promt and I gets this failure:

warning: variable "tooth_wheel_width2" in config_t not found

what can be the problem?

A: It probably means that you have a variable in in your config.txt that is not there in firmware config_t (names dont match or it is not there altogether)

Q: Is there anybody who has the Megatune 2.25, that could mail it to me, because the link on the site does'nt work.

My mail is: m_franck@webspeed.dk

Q: * Do I need too calibrate my map-sensor, I am using a 2bar Webber Marelli from a ford sierra cosworth.

2bar = 200 kPa so kpafac=64 (decimal 100) should be good.

No need to calibrate, IMHO, but you can checkout the local pressure in the radio/internet weather forecast or homepage of your airport. Adjust kpafac accordingly. You won't know exact kpaofs unless you have a calibrated vacuum source: so just guess kpaofs. Any kpaofs will work. After tuning the engine, don't change kpafac too much, because it will effect the tuning If you do, adjust req_fuel in the opposite direction.

Q: Tachometer problems, my tachometer does not showe the correct RPM because I am using wasted spark, can I connect the Tachometer to the V3-controller an get the correct RPM, ore are the other obsentions ?