deleted

[Kricke]

deleted...........

[pikeslayer]

Seems like a lot of effort on the moco's part to use the MAP sensor to trigger the injector.  From the moco's point of view, valve events never change.  I would think they would just come up with a new calibration file for each SE cam.  Maybe this is why everyone suggests picking a calibration file that closely matches the cam you are running?

On another note, how does the ECM know what stroke a cylinder is on.  Crank sensor is only gonna tell it one of 2 possibilities.  For instance, it will know the piston is coming up, but it won't know whether it's coming up on the exhaust or compression from crank sensor data alone.  That only leaves the ion sense, or the MAP sensor to determine strokes.

No expert here, just trying think my way through it.

[FLTRI]

DM,
Not sure why you are doubting Doc. He is an experienced, knowledgeable tuner who knows what he is talking about and is only here to help those who ask. I also tune for a living and can verify Doc's information.
While I realize you (and others) may have your own ideas and/or doubts as to how the Delphi system functions, it actually works just as Doc stated.
If you are looking for information here you must be willing to learn as well. Here perception is not always reality.
Hope this helps,
Bob

[FLTRI]

If the injectors are controlled as Doc says, why will the engine run with the MAP sensor disconnected?

Oh it will run, just run like crap because the only thing the system has to go off for timing is the crank sensor. Remember, all EFI systems have a "limp" mode that will keep the engine running to get it to a shop.
Bob 

[Doc 1]

If the injectors are controlled as Doc says, why will the engine run with the MAP sensor disconnected?

Oh it will run, just run like crap because the only thing the system has to go off for timing is the crank sensor. Remember, all EFI systems have a "limp" mode that will keep the engine running to get it to a shop.
Bob  

Thanks Bob but as you can see this is going no where.
If you guys want information on writen on paper from the MoCo or Delphi,  then you shouldn't ask on a forum...duh!  Pick up the phone and call them...there should be someone you know that will dial the phone for you.

The ECM is a computer jabarr and computer STORE events that are happening and has happened so it remains running....duh!

Ever since we lost the cam position sensor the MAP sensor has taken on the responsability of the cam position sensor, the actual triger to the injector is stored information of the pulse width required, MAP Sensor locating the stroke, and TDC from the CKP, then the code is written to trigger the injector....you can't and will not be able to change the codes in behind the scenes to alter the begining of the pulse width.......BOTTOM LINE.  The only thing you can do is select a map with the closest characteristics to the cam your running and hope it gives you the best power and keeps you in the emmission standards, if not select another map and try again.
I deleted my post on this subject because of the idot magnet it has become...I tried to explane it to you in the simplest way I knew how, now I'm done with it.
Doc  

[jabarr]

"I deleted my post on this subject because of the idot magnet it has become...I tried to explane it to you in the simplest way I knew how, now I'm done with it.
Doc "

I knew better than to attempt to ask a real question here!
Now everyone that is trying to understand the system is an idiot?  Jeez Doc--that is really trying to help those that are merely asking how the system ACTUALLY works!!  I for one would love to    if you could please direct me to the location of this bible if it exists.  "

[pikeslayer]

That's a real bummer.  Seems every time I try to dig deeper to learn something some one gets pissed because instead of bowing to them I ask questions.

Back to the issue:

I actually believe Doc.  Mainly because after pondering this awhile, I can't think of any other explanation of how the engine knows what stroke it's on.

Wrap your noodle around this:

Set the rev limiter to 3500 rpm.  Open the throttle the whole way.  Start the bike.  The MAP sensor will see atmospheric pressure the whole time (no pulse from the intake valve).  Will it know what stroke it is on?

[Doc 1]

"I deleted my post on this subject because of the idot magnet it has become...I tried to explane it to you in the simplest way I knew how, now I'm done with it.
Doc "

I knew better than to attempt to ask a real question here!
Now everyone that is trying to understand the system is an idiot?  Jeez Doc--that is really trying to help those that are merely asking how the system ACTUALLY works!!  I for one would love to    if you could please direct me to the location of this bible if it exists.  "

You didn't ask a question jabarr....you made a statment...! Thanks for the email you sent me ...... I'll just share it with everyone else;
edited by Coyote - The PM has been dealt with. This ends now.

[Steve Cole]

I'm not going to get into this as the answers are already out there for the most part. The hows and why's go much deeper than 99% of you would understand or care about. Doc has the general idea down pretty good and you guys should let it go already. I just do not have the time to write a 30 page response as to how it all works when the general information is posted already. Is there more to it........... sure, and it's taken me 10 years to learn and understand it so that we could set things up here in the base calibrations. Pick a base calibration that most closely matches your camshaft and compression ratio to begin with. Then move on to the exhaust and air cleaner. If it's for a different displacement then just adjust it for what you have.

[FLTRI]

I for one would love to    if you could please direct me to the location of this bible if it exists.  "

jabarr,
Unfortunately education costs $$. You either get it by O.J.T.,reading books, or paying someone to teach you. In any event, it's not free.
Take a look here for your answers:
http://www.efi101.com/about.html
HTH,
Bob
PS - I believe the problem with this thread is a question was asked, then a qualified member offered the answer, yet was challenged by someone without knowledge or experience.

[Coyote]

PS - I believe the problem with this thread is a question was asked, then a qualified member offered the answer, yet was challenged by someone without knowledge or experience.

I agree.

[pikeslayer]

I spent 4 years programming Honda ECU's and running a dyno for them.  Now this definitely doesn't make me an expert, but I think it at least gives me the right to ask questions.

So, I guess most of you think that it is common for an EFI system to use the MAP sensor to determine stroke.  This is the first time I had heard of this.  Hence the question.  Sorry if I offended, definitely wasn't the intention.

Let's try this again, back to the issue:

So what about the wide open throttle scenario I outlined above?  Would there be enough of a pulse generated at WOT and 3500 rpm?

[pikeslayer]

Yet another theory!!!  Found this thread.  It's long, so if you don't want to read it, I'll summarize.  These guys are wondering how an Aprilla twin cylinder engine figures out what stroke it is on without employing a cam sensor.  Nobody seems to know, but they offer the theory that the ECM senses a slow down in cranking speed during starting and can determine which cylinder is on compression.

Very interesting.

http://www.apriliaforum.com/forums/showthread.php?t=173964

[pikeslayer]

Here is a copy and paste from that Aprilla forum:

"The ECU synchs the crank sensor to the compression TDC with algorithm logic.
During the start cycle, the ECU fires on every TDC until it detects an increase in rotation speed caused by a successful combustion."

Kinda similar to my previous post, but a little different.  Good stuff!

[Steve Cole]

You do not have to guess where your at once the motor is started, you already know! The system only needs to figure out the difference between BDC and TDC at start up.