Toyota COP dwell curve
#42
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Here is a screen shot of how I modified my AEM EMS Cal for the toyota COP's. I used the formula from the AEM forum as follows:
Dwell time = (0.02 * Dwell Factor * Dwell Vs. RPM * Dwell Vs. Batt Voltage)/1000
I used Excell to figure out how to modify the Dwell Vs. Batt table after using the Coil Wizard to select the toyota 04 up prius.
I'd be interested to see how you guys with AEM's modified your tables to set Dwell. Seems like you could change any one of the 3 variables to achieve the same goal. I also just made an assumption that the curve would follow smoothly below 9 volts.
I have not started the car yet, so I cannot claim this worked yet.
Dwell time = (0.02 * Dwell Factor * Dwell Vs. RPM * Dwell Vs. Batt Voltage)/1000
I used Excell to figure out how to modify the Dwell Vs. Batt table after using the Coil Wizard to select the toyota 04 up prius.
I'd be interested to see how you guys with AEM's modified your tables to set Dwell. Seems like you could change any one of the 3 variables to achieve the same goal. I also just made an assumption that the curve would follow smoothly below 9 volts.
I have not started the car yet, so I cannot claim this worked yet.
#43
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So that all the dwell measurments I made are in the same place, here are the Inifniti COP dwell curves.
Marking says
Hanshin
MCP-1350
It has a 3 wire connector
The COP has labels "IB G +" which refers to input, ground, 12V.
The input requires at least 2.5V and 3.6 mA to that it will current limit at at least 6A. More drive results in higher current limit but it's diminishing returns.
For example it will current limit at 7A if driven to 3.2V / 23 mA.
The input should not be driven without a current limiting resistor. From a 5V drive 220 to 680 ohms will work. From a 12V drive, 1k to 1.5k will work.
Note that some ECU outputs will have a current limited drive and this may need to be considered.
To trigger a spark the input needs to go below 0.7V minimum. A high impedance low state is OK.
The primary inductance is 3.1 mH
The resonant freq appears to be 31 kHz
Here are the dwell numbers for 5.5A peak current (94 mJ primary energy)
8 V 2.5 ms
10V 1.75 ms
12V 1.43 ms
14V 1.2 ms
16V 1.06 ms
At 5.5A of primary current and using a 1 kV zener on the output, secondary energy is ~50 mJ.
Peak secondary current is 55 mA and falls to zero in 2 ms.
With an open secondary peak secondary voltage is 35 kV at 5.5A primary current.
Spark delay is 12 us signal delay, + 35 us output voltage rise time.
Rise time to 20 kV is 13 us.
Marking says
Hanshin
MCP-1350
It has a 3 wire connector
The COP has labels "IB G +" which refers to input, ground, 12V.
The input requires at least 2.5V and 3.6 mA to that it will current limit at at least 6A. More drive results in higher current limit but it's diminishing returns.
For example it will current limit at 7A if driven to 3.2V / 23 mA.
The input should not be driven without a current limiting resistor. From a 5V drive 220 to 680 ohms will work. From a 12V drive, 1k to 1.5k will work.
Note that some ECU outputs will have a current limited drive and this may need to be considered.
To trigger a spark the input needs to go below 0.7V minimum. A high impedance low state is OK.
The primary inductance is 3.1 mH
The resonant freq appears to be 31 kHz
Here are the dwell numbers for 5.5A peak current (94 mJ primary energy)
8 V 2.5 ms
10V 1.75 ms
12V 1.43 ms
14V 1.2 ms
16V 1.06 ms
At 5.5A of primary current and using a 1 kV zener on the output, secondary energy is ~50 mJ.
Peak secondary current is 55 mA and falls to zero in 2 ms.
With an open secondary peak secondary voltage is 35 kV at 5.5A primary current.
Spark delay is 12 us signal delay, + 35 us output voltage rise time.
Rise time to 20 kV is 13 us.
Last edited by JasonC SBB; 06-12-2009 at 10:21 PM.
#47
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Schematics are here: MegaManual Index ... I'm not sure which is the correct one. (DIY built mine - v. 3.5.7)
#53
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More data. I will type it here for posterity. If I keep it in a notebook I will more likely lose it.
Toyota coils
------------
primary L: 4.7mH below 5.2A, 1.6 mH above
current limit: 10A
delay from signal to beginning of output voltage rise: 6 uS
rise time to 20 kV: 12 uS
peak voltage: 37kV
rise time to 37kV: 48uS
2001 coils:
-----------
primary L: 7mH
current limit: 6.5A
delay: 6uS
rise time to 20 kV: 25 uS
peak V: 25kV
rise time to 25 kV: 65 uS
'00 coils:
--------
primary L: 10 mH
current limit: 6A
delay: 8 uS
rise time to 20 kV: 13 uS
peak V: 36kV
rise time to 36kV: 38 uS
TEC3 coils:
----------
primary L: 3mH
current limit: 5A engine idling with the TEC running
rise time to 20 kV: 9uS
rise time to peak of output: 30 uS
peak output at 4A of current is 35kV
peak output at 5A of current is 40 kV (limit of the high voltage probe)
The TEC coils appear to have a very high output voltage indeed. It seems to have a high turns ratio, and low capacitance. This would also translate to a lower current spark but long duration (with a high peak voltage capability of igniting hard-to-ignite mixtures)
TThe '00 coils are good.
The Toyota coils are good but don't have the same energy storage as the '00 coils.
The '01 seems lousy in comparison, in terms of peak voltage capability and delay. At 7200 RPM, there are 23 uS per degree of timing. If this translates to any real-world performance loss, I don't know.
Toyota coils
------------
primary L: 4.7mH below 5.2A, 1.6 mH above
current limit: 10A
delay from signal to beginning of output voltage rise: 6 uS
rise time to 20 kV: 12 uS
peak voltage: 37kV
rise time to 37kV: 48uS
2001 coils:
-----------
primary L: 7mH
current limit: 6.5A
delay: 6uS
rise time to 20 kV: 25 uS
peak V: 25kV
rise time to 25 kV: 65 uS
'00 coils:
--------
primary L: 10 mH
current limit: 6A
delay: 8 uS
rise time to 20 kV: 13 uS
peak V: 36kV
rise time to 36kV: 38 uS
TEC3 coils:
----------
primary L: 3mH
current limit: 5A engine idling with the TEC running
rise time to 20 kV: 9uS
rise time to peak of output: 30 uS
peak output at 4A of current is 35kV
peak output at 5A of current is 40 kV (limit of the high voltage probe)
The TEC coils appear to have a very high output voltage indeed. It seems to have a high turns ratio, and low capacitance. This would also translate to a lower current spark but long duration (with a high peak voltage capability of igniting hard-to-ignite mixtures)
TThe '00 coils are good.
The Toyota coils are good but don't have the same energy storage as the '00 coils.
The '01 seems lousy in comparison, in terms of peak voltage capability and delay. At 7200 RPM, there are 23 uS per degree of timing. If this translates to any real-world performance loss, I don't know.
They had long skinny shafts and a larger body than the Toyota COPs, and are a bit clumsy fit in the 99 cam cover, seemingly hopeless for the 01 cam cover. Their markings were "Hanshin MCP1350", no Nissan logo or part number
Brief disucssion of fitment was here
https://www.miataturbo.net/megasquirt-18/01-cops-ms-32827/
In my own language lol
Input is proportional (e.g. not comparator’ed / schmitt’ed)
Current limit can be 6-8A depending on drive
e.g.
5A if 2.2V @ 1.7 mA
6A if 2.5V @ 3.6 mA (not recommended to go below this drive)
7A if 3.2V @ 23 mA
7.7A if 4.2V @ 53 mA
drive requriements, assume 5 mA @ 2.5V (output impedance with 5V drive <500 ohms)
Off drive minimum is ~0.8V (drive output V must go below this)
Delay time, trigger fall to start of steep rise in HV – 12 us
With large currents, rise time of HV is 9us
Resonant frequency is 31 kHz
6A Lab supply with 10mF bypass testing
Cur lim = 6.5A
Initial inductance is 3.1 mH
Current rise is very straight.
Dwell times, for 5.5A primary peak current: (94 mJ input energy)
8 V 2.8 mS
10 V 1.78 mS
12 V 1.44 mS
14 V 1.17mS
secondary waveform testing
With 1 kV TVS load
5.5A pri ~55 mA peak sec current, 2 mS ramp down time, ~55 mJ.
(calc est 100:1 turns ratio)
2A primary peak current yields 13 kV pk, unloaded
3A 20 kV
4A 25 kV
5.2A 32 kV @ 35 uS rise time
#54
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Speaking of dwelbs
Did you guys fry your COPS yet ?
I was running mine for a while on the stock ECU without a dwell reducer.
Recently I went back to using the MS and while switching MSQs on my the motor immediately started missing.
After switching to the OEM coils back again everything was fine then I tried the COPs again and two are not firing
The wiring and connections are fine far as I can tell
![](https://www.miataturbo.net/images/smilies/bowrofl.gif)
I was running mine for a while on the stock ECU without a dwell reducer.
Recently I went back to using the MS and while switching MSQs on my the motor immediately started missing.
After switching to the OEM coils back again everything was fine then I tried the COPs again and two are not firing
The wiring and connections are fine far as I can tell
#60
Former Vendor
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Having said that, at least two of the coils in my car lived through that and appear to be just fine.