What is the type of cam and crank pattern used on Evo ix ?
What is the type of cam and crank pattern used on Evo ix ?
In my quest for a new ecu I've been looking for the correct terminology for our trigger/reluctor set up.
I don't believe it's a 36-1 or a few others and I think it's like the odd man out on a lot of compatibility lists
I don't believe it's a 36-1 or a few others and I think it's like the odd man out on a lot of compatibility lists
2 pulses per revolution on the crank and cam (thus 1 pulse per crank revolution on the cam). The duration and phase of the pulses is the important part.
I can't remember if it is the raising or falling edge electrically, but the end of the metal plate is 5*BTDC. The starting edge is like 75* or so, it has been a while since I looked at it.
On the cam, there is a longer pulse on one of the cycles then the other and possibly slightly different phase. The end results is that the ECU can determine the exact cycle position of the motor on any given crank pulse before it has to fire the plug.
Most aftermarket ECUs do not take advantage of this phase scheme though and simply require the engine to cycle 2 complete rotations before properly syncing to the engine.
It's also a hall effect sensor on both sensors, so you are dealing with a digital signal, not a reluctor type signal.
Also, this is specifically for ignition and fuel timing. With regards to the IX specifically, I'm not sure how the second cam sensor fits in to this. Considering the similarities in the ECU code under the main ignition/injection interrupt though, I have to imagine it works the same way and the second sensor is specifically for cam timing alone.
I can't remember if it is the raising or falling edge electrically, but the end of the metal plate is 5*BTDC. The starting edge is like 75* or so, it has been a while since I looked at it.
On the cam, there is a longer pulse on one of the cycles then the other and possibly slightly different phase. The end results is that the ECU can determine the exact cycle position of the motor on any given crank pulse before it has to fire the plug.
Most aftermarket ECUs do not take advantage of this phase scheme though and simply require the engine to cycle 2 complete rotations before properly syncing to the engine.
It's also a hall effect sensor on both sensors, so you are dealing with a digital signal, not a reluctor type signal.
Also, this is specifically for ignition and fuel timing. With regards to the IX specifically, I'm not sure how the second cam sensor fits in to this. Considering the similarities in the ECU code under the main ignition/injection interrupt though, I have to imagine it works the same way and the second sensor is specifically for cam timing alone.
Last edited by 03whitegsr; Mar 29, 2013 at 09:38 PM.
My question is will a ms3-pro decode this?
http://www.diyautotune.com/downloads...pro_manual.pdf
Page 37, does the ix fall in any of those? I really don't think so. But my Google fu is weak on this one
DIY auto tune asked me the cam crank set up and I'm not sure how to word it. I know how it work but not what's called
http://www.diyautotune.com/downloads...pro_manual.pdf
Page 37, does the ix fall in any of those? I really don't think so. But my Google fu is weak on this one
DIY auto tune asked me the cam crank set up and I'm not sure how to word it. I know how it work but not what's called
I think one way to deal with this is cutting off one of the cam teeth. Thus when the crank goes high and the cam is high, it's cylinder one. Then worse case, the engine has to rotate 2 times before it can fire the first spark.
Otherwise, you could use some logic to figure it out.
***Note the numbers in those charts do not represent cylinder number!!!***
Cam is high during rising and falling edge of #1
Cam is low at rising edge and high at falling edge of #3
Cam is High at rising edge and low at falling edge of #4
Cam is low during rising and falling edge of #2
I BELIEVE that during cranking, the ECU basically ignores the rising edge of the signal and only uses the falling edge of the crank signal (thus mechanically locking ignition advance at 5*). I think the same happens in the diagnostics mode where it locks timing at 5*. You could potentially do the same on an aftermarket ECU to allow the logic analysis above on start up.
FWIW, I think the OEM relies heavily on the rising edge of the crank for most of the ignition and fuel and then uses the falling edge heavily in the misfire detection stuff. But I could be wrong, that section of the OEM code is extremely complex when looking at it in IDA.
Otherwise, you could use some logic to figure it out.
***Note the numbers in those charts do not represent cylinder number!!!***
Cam is high during rising and falling edge of #1
Cam is low at rising edge and high at falling edge of #3
Cam is High at rising edge and low at falling edge of #4
Cam is low during rising and falling edge of #2
I BELIEVE that during cranking, the ECU basically ignores the rising edge of the signal and only uses the falling edge of the crank signal (thus mechanically locking ignition advance at 5*). I think the same happens in the diagnostics mode where it locks timing at 5*. You could potentially do the same on an aftermarket ECU to allow the logic analysis above on start up.
FWIW, I think the OEM relies heavily on the rising edge of the crank for most of the ignition and fuel and then uses the falling edge heavily in the misfire detection stuff. But I could be wrong, that section of the OEM code is extremely complex when looking at it in IDA.
Last edited by 03whitegsr; Mar 29, 2013 at 09:54 PM.
If you cut off the smaller tooth on the cam, then it's simply 2 pulses per crank revolution on the crank and 1 pulse per engine cycle on the cam. Most ECUs should have no trouble handling that.
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Gotcha
Still would like to know if the megasquirt has ever or can run a Evo 9 in oe cam crank config
Last edited by 211Ratsbud; Mar 29, 2013 at 10:01 PM.
The 1G stuff I'm not sure about. I THINK it uses the same angles (in theory), but because it was really a cam angle sensor with two different trigger plates and sensors, you had issues with t-belt stretch that caused timing variance with RPM and engine acceleration rates. I believe this was the case for the missfire issues when using a 1G CAS in the 1Gina2G swaps anyway.
Pretty sure the 2G setup is the same as the EVO, save for the '95s that had the trigger plate on the front of the cam. I think they used basically the exact opposite phasing, thus you had to swap plugs around when using the EPROM ECUs in the '97-on 2G dsms for DSMLink V1. They later accomplished the same thing through software in V2.
Pretty sure the 2G setup is the same as the EVO, save for the '95s that had the trigger plate on the front of the cam. I think they used basically the exact opposite phasing, thus you had to swap plugs around when using the EPROM ECUs in the '97-on 2G dsms for DSMLink V1. They later accomplished the same thing through software in V2.
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