Omex 200 - mapping procedure?
Discussion
I have an Omex 200 fitted to my Seven - it is working very well, and the map seems good...
I'm running twin 45s, so am using the Omex just for the ignition (no other sensors being used other than for timing and tps - no water temp, exhaust, air...).
I can connect my laptop to the Omex and see all the relevant data being reported, and have set tps, as well as making sure the default setting for the sensors I am not using do not interfere with the engine running (the default low-temp water setting need changing for example).
I've read the Omex manuals, but can't really work out the workflow I need to use to record engine data while driving, and then using that data to see if the map can be improved in any way.
I know I can go get this done on a rolling road, but I'm keen to have a look myself to see if the map good or not before I decide to do that.
Any help appreciated.
I'm running twin 45s, so am using the Omex just for the ignition (no other sensors being used other than for timing and tps - no water temp, exhaust, air...).
I can connect my laptop to the Omex and see all the relevant data being reported, and have set tps, as well as making sure the default setting for the sensors I am not using do not interfere with the engine running (the default low-temp water setting need changing for example).
I've read the Omex manuals, but can't really work out the workflow I need to use to record engine data while driving, and then using that data to see if the map can be improved in any way.
I know I can go get this done on a rolling road, but I'm keen to have a look myself to see if the map good or not before I decide to do that.
Any help appreciated.
The issue with "improving" the ignition mapping on the road is that there is little way of telling if you are actually making any improvements!
There are basically 3 main areas that require work:
1) MBT timing: this is the portion of the ignition map where spark timing is NOT limited by detonation. MBT stands for Minimum Best Timing, and that is effectively what you need to get. Under or over advancing the ignition will both reduce BMEP
2) BLD timing: Boarder Line Detonation timing. the areas where you try to advance to MBT, but before you get there detonation occurs limiting the maximum advance. Typically these zones are large throttle openings at low to medium rpm.
3) Transient and driveability spark: Generally either smoothing the joins between different operating points, or deliberately flatening timing values to introduce torque stability (say around idle rpm etc)
Without any torque feed back (rolling road/chassis dyno) generally you can only really work on 3), and maybe 2) depending on how detonation prevalent your engine is (and how brave you are feeling!)
Also, with just TPS and rpm inputs, most of the fine optimisation for things like warm up correction, IAT corrections, etc can actually be achieved.
Most "diy" spark maps tend to suffer from underadvanced light load MBT values, where the low cylinder filling leads to very slow burn rates and hence requires very advanced ignition angles. Beware however, over advance at light loads can lead to "pre ignition" which is an early spontaneous burn of the charge, which unlike detonation occurs well before TDC and so generally cannot be heard, yet can still be extremely damaging.
The other thing to note is that with TPS based load determination, the concept of "effective wide open throttle" needs to be considered. This is basically an effect where the throttle angle that results in full load (MAP = BARO) is reduced as engine rpm reduces. Effectively the throttle becomes bigger as rpm falls, so for example you might find that at say 1500rpm, WOT occurs at as little as 30% TPS angle ! Your ignition map needs to reflect this characteristic.
There are basically 3 main areas that require work:
1) MBT timing: this is the portion of the ignition map where spark timing is NOT limited by detonation. MBT stands for Minimum Best Timing, and that is effectively what you need to get. Under or over advancing the ignition will both reduce BMEP
2) BLD timing: Boarder Line Detonation timing. the areas where you try to advance to MBT, but before you get there detonation occurs limiting the maximum advance. Typically these zones are large throttle openings at low to medium rpm.
3) Transient and driveability spark: Generally either smoothing the joins between different operating points, or deliberately flatening timing values to introduce torque stability (say around idle rpm etc)
Without any torque feed back (rolling road/chassis dyno) generally you can only really work on 3), and maybe 2) depending on how detonation prevalent your engine is (and how brave you are feeling!)
Also, with just TPS and rpm inputs, most of the fine optimisation for things like warm up correction, IAT corrections, etc can actually be achieved.
Most "diy" spark maps tend to suffer from underadvanced light load MBT values, where the low cylinder filling leads to very slow burn rates and hence requires very advanced ignition angles. Beware however, over advance at light loads can lead to "pre ignition" which is an early spontaneous burn of the charge, which unlike detonation occurs well before TDC and so generally cannot be heard, yet can still be extremely damaging.
The other thing to note is that with TPS based load determination, the concept of "effective wide open throttle" needs to be considered. This is basically an effect where the throttle angle that results in full load (MAP = BARO) is reduced as engine rpm reduces. Effectively the throttle becomes bigger as rpm falls, so for example you might find that at say 1500rpm, WOT occurs at as little as 30% TPS angle ! Your ignition map needs to reflect this characteristic.
Edited by anonymous-user on Friday 7th October 20:24
I have all the Omex documents, but they do not describe the 'workflow' for logging and map adjustment from the logged data. They just describe the various functions in basic form.
I was hoping for some help from someone who has used the MAP3000 software to help me get started.
Anyone able to give their experience?
I was hoping for some help from someone who has used the MAP3000 software to help me get started.
Anyone able to give their experience?
Then as with pretty much any ecu, there should be a very simple menu system with an option to save any datalogs.
of course....there is always the "read the user manual" option ?
Whilst Ive never used Omex, I find it hard to believe you've communicated with the ecu via laptop, and cannot find what you are looking for.
Either referencing to the instruction manual, or built in help files that virtually every system uses
of course....there is always the "read the user manual" option ?
Whilst Ive never used Omex, I find it hard to believe you've communicated with the ecu via laptop, and cannot find what you are looking for.
Either referencing to the instruction manual, or built in help files that virtually every system uses
Surely any log you can see will tell you only RPM, throttle position and ignition advance. It won't tell you about what the engine is doing - knocking, pre-igniting, misfiring.
Really you need to be running the engine on a dyno, and then you don't need the log in the first place.
Max Torque - I thought MBT was "Minimum Advance for Best Torque", and essentially means that around 'optimum' timing there is little change in BMEP, so you choose the least advance before output is noticeably effected, which gives more knock safety. At least you didn't call it Minimum Best Torque which a lot of boyracers think it means, that doesn't actually make sense.
Really you need to be running the engine on a dyno, and then you don't need the log in the first place.
Max Torque - I thought MBT was "Minimum Advance for Best Torque", and essentially means that around 'optimum' timing there is little change in BMEP, so you choose the least advance before output is noticeably effected, which gives more knock safety. At least you didn't call it Minimum Best Torque which a lot of boyracers think it means, that doesn't actually make sense.
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