Raw number to ms injection time conversion

bulardas · Newbie

Raw number to ms injection time conversion

RidgeRacer · Guru

Just so we are on the same page....

Some people refer to the 32b 7052 as gen I where as I think the correct way is 16b = Gen I, 7052 32b = Gen II, and M32R = Gen III

I believe the GenII unit is 2uS i.e. a value of 500 = 1mS of spray.

I would think the easiest way to figure the GenI unit would be to compare similar areas of the fuel maps to a GenII. It is most likely multiplied by some power of 2.

If you divide the GenII numbers by their matching GenI numbers and you get values like 127.47, 128.83, etc. Just go with 128

RidgeRacer · Guru

I just compared the ZX-12 GenI to the GenII and it looks like Gen1 map * 16 = Gen2 map

So GenI * 32uS = Injector time.

bigtoe · Senior Member

RidgeRacer wrote:
I just compared the ZX-12 GenI to the GenII and it looks like Gen1 map * 16 = Gen2 map

So GenI * 32uS = Injector time.

Are you suggesting that the OP take the number from the Gen 1 fuel maps in ECUEDITOR, multiply by 32uS to get the injector time?

RidgeRacer · Guru

Not being a user of ECUeditor myself I sometimes forget that most Busa tuners use that as their frame of reference.

So on a 'Gen I' busa ('02-'07 Sh7052 32bit ECU) the fuel map units displayed in ECUeditor are the actual binary map values divided by 24.

ECUeditor value x 24 = 'Denso value'. Denso x 2uS = injector time

or

value x 48uS = Injector time.

Of course this is the base value. The actual signal pulse measured at the injector will be something like:

(Base x IATcomp x ECTcomp x SAPcomp x Trim(Yosh) + Latency + QuickThrottleEnrichment

I should be clear I have never verified the 2uS through actual measurement. It is based on looking at the software and how the MCU timer prescalars and crystal PLL are setup. I am fairly confident with that figure as the base I/O clock is also used for the serial baud rate generators. My math checks out with the known baud rates used by the ECU so I am assuming the injector, coil math is correct as well.

bulardas · Newbie

What i don't understand is why you say Gen1 to a 32bit ECU?
The ECU i'm interested in is the 16bit Gen1 Busa.

And another question is, does Woolich Racing using a different scaling for the fuel maps?

I have to open some bins in raw format and look what numbers are inside.

But what i understood from here since now is that the raw value of Gen2 (not M32R) means 2us. Is this true?

RidgeRacer · Guru

bulardas wrote:
What i don't understand is why you say Gen1 to a 32bit ECU?
The ECU i'm interested in is the 16bit Gen1 Busa.

And another question is, does Woolich Racing using a different scaling for the fuel maps?

I have to open some bins in raw format and look what numbers are inside.

But what i understood from here since now is that the raw value of Gen2 (not M32R) means 2us. Is this true?

In the Hayabusa community the majority of people use ECUeditor. If you go to ecueditor.com you will see they flash "Hayabusa Gen1, Gen2, Bking, GSXR..." The EcuEditor community thinks k2-k7 32b ECUs are Gen1. Until your last post I didn't know which group you were in.

As the 32b SH7052 and 32b M32R use the same time units for the rest of this thread I will use 16b and 32b to refer to the different ECUs

I compared the 16b fuel maps to the 32b in the busa and it looks like they are 16b maps * 32 = 32b maps.

That would make the 16b injector time x 32 x 2uS or 64uS

jkwool · Guru

bulardas wrote:
What i don't understand is why you say Gen1 to a 32bit ECU?
The ECU i'm interested in is the 16bit Gen1 Busa.

And another question is, does Woolich Racing using a different scaling for the fuel maps?

I have to open some bins in raw format and look what numbers are inside.

But what i understood from here since now is that the raw value of Gen2 (not M32R) means 2us. Is this true?

The fuel numbers in ecueditor are the raw numbers from the bin file map divided by 24, i think this was done to make the numbers smaller in the fuel maps. The fuel numbers in the Woolich Racing Tuned software are the raw numbers taken from the map in the bin file with no modification. We did it that way so you dont loose any resolution when editing the fuel maps.

bigtoe · Senior Member

RidgeRacer wrote:
Not being a user of ECUeditor myself I sometimes forget that most Busa tuners use that as their frame of reference.
I should be clear I have never verified the 2uS through actual measurement. It is based on looking at the software and how the MCU timer prescalars and crystal PLL are setup. I am fairly confident with that figure as the base I/O clock is also used for the serial baud rate generators. My math checks out with the known baud rates used by the ECU so I am assuming the injector, coil math is correct as well.

What you have wrote I believe is a much better answer. Not sure how the OP will use this info. As you suggest, it is not a simple thing to calculate.

For a 32-bit Gen 1, Pulse width(seconds) = (ECUeditor value x 48uS x IATcomp x ECTcomp x SAPcomp x Trim(Yosh) + Latency + QuickThrottleEnrichment

ECUEditor, selecting a stock map, At 100% throttle, I see the following in their TPS fuel map:

3000 RPM @ 100% TP = 145, or 6.98mS base using your numbers.

10000 RPM @ 100% TP = 194, or 9.31mS base using your numbers.

With my simulator setting both AP and IAP to 90KPa, coolant temp and air temp to 27C, TPS at 100%,

At 3000 RPM I measure 7.895mS with the simulator. ECUEditor shows FUEL pw is 135. May data logger using serial bus reads 7.776.

With the coolant at 140C, the simulator measures 6.965mS. ECUEditor shows FUEL pw is 110. My data logger reads 6.856.

At 10000 RPM I measure 9.857mS with the simulator. ECUEditor shows FUEL pw is 183. My data logger reads 10.014.

With the coolant at 140C, the simulator measures 8.662mS.

I thought I would add what my data logging software shows compared to ECUEditor. I have seen cases where ECUEditor will show a negative FUEL pw. Hope this helps.

-- Edited by bigtoe on Sunday 9th of March 2014 01:59:45 AM

bigtoe · Senior Member

Looking at the ECUEditor negative fueling, it appears to remain at -48 until the engine speed reaches between 700 and 800 RPM. It will then start updating. It then latches the fuel number when it reaches between 400 and 300 RPM. Once the number is positive, I can't find a way to get it negative. Without looking at the software, I would guess how ever they do the conversion, 0 = -48.

bigtoe · Senior Member

From the ECUEDITOR source code:

'FUEL = CInt(((b(8) * 256) - 1024) * 2.47 / 100) * 2 ' if 48, then *1, if 24 then*2
'FUEL = Int(((b(8) * 12.8) - 64))
Fuel = Int(((b(8) * 12.2) - 48))

Looks like they were trying different things to get the numbers to work out right. So when the ECM sets the fuel PW to zero, 0 X 12.2 - 48 = -48. Not right but at least it makes sense why I see a negative number.

I didn't spend much time looking at the source. There were enough problems with it that I just started over. When I did my logger I never saw where I needed to do any real fudging of the numbers. The fuel pulse width, RPM, timing are pretty much a direct read in the correct units already. I just display them.

Sorry to derail your original question OP.