IDM mod. Does it work?
#46
04-06-2008, 02:52 PM
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thanks for the info Scott..let me get this strait..you de soder the resister that is built into the board shown in pic where the green and yellow wire is..and them 2 wires are added in with a new resister correct?? if so..i see the resister has a brown stipe on one end..if i did this just like the pic...witch way does the brown stipe on the resister go??? or does it do its job ether way?? i know diods only work one way..im not great with electronics so please excuse so many questions...
#47
04-06-2008, 02:59 PM
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ron.....adding the wires are only for a switch to turn the mod on/off. It is not necessary and is not recommended on the site with the pics from what I read. As far as resistor direction, I'm not sure......if you do not get an answer here, I would ask the supplier if it goes both ways........LOL
#48
04-06-2008, 03:19 PM
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ron.....adding the wires are only for a switch to turn the mod on/off. It is not necessary and is not recommended on the site with the pics from what I read. As far as resistor direction, I'm not sure......if you do not get an answer here, I would ask the supplier if it goes both ways........LOL
above for your model IDM. (Should be a sticker that lists the model near the connector).
In the pics I have, you would solder to the same place on the board that the green and yellow
wires are soldered. You shouldnt use wires or switches.
#49
04-06-2008, 04:35 PM
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Awhile back I did some analyses of the IDM vs injection timing that might be of interest here. All the nitty gritty can be found in the link below, and I'll just summarize a few points here.
pulse width and pcm/idm signals
https://www.ford-trucks.com:80/forum...m-signals.html
It's clear to me from the above, that the IDM mod will advance the "effective" timing some, and therefore the use of this mod should be accounted for in the overall tuning, as in with a DP program.
pulse width and pcm/idm signals
https://www.ford-trucks.com:80/forum...m-signals.html
...Ok, I spent some time with some help of a friend playing with the IDM and a scope today. From the way it looks the PCM is sending 2 signals per injection event to the IDM.
I also Measured the output voltage while runing and was very shocked on how low the actaul output to the injectors are compared to what i have read the working voltage is. My stock 120 IDM was only putting out 66 volts to the injector Noting near the often qouted 120 volts...
I also Measured the output voltage while runing and was very shocked on how low the actaul output to the injectors are compared to what i have read the working voltage is. My stock 120 IDM was only putting out 66 volts to the injector Noting near the often qouted 120 volts...
...I read that the IDM has it's own little onboard computer/microprocessor, and that the PCM sends the IDM digital words which instruct the on and off time for each injector pulse. I think the two signals you see are the one word for on and the other word for off. Also, the off pulse is reverse polarity to drive the solenoid in the off direction.
...The PCM programming controls the Injection Time IT*=crank degrees, and the injection Pulse Width, PW*=crank degrees. These parameters control the timing and the amount of fuel injected, and this in turn tailors the peak combustion pressures in the vicinity of TDC, and this is what determines the cylinder MEP and resulting HP.
To program for maximum HP, you want to control the IT* and PW* to maximize MEP at each RPM. Of course the Ford PCM programming has to worry about other things as well, including emissions, MPG, and reliability.
At 3000 RPM, for example, each crank deg is 55.55 usec. At 3000 RPM, an impulse (zero time width) injection at 30* BTDC, is followed by a 20* ignition delay, then a 5* delay as pressure rises to a maximum, so maximum occurs at 5* BTDC. The actual pulse width, PW, is about 555.5 usec, so that fuel is injected over a 10 deg interval of crank degs. Therefore, fuel injection occurs from 30* to 20* BTDC, then 10* to 0* BTDC for initiation of burn, and maximum pressure at 5* BTDC to 5* ATDC, and this gives maximum cylinder MEP and thus HP.
To program for maximum HP, you want to control the IT* and PW* to maximize MEP at each RPM. Of course the Ford PCM programming has to worry about other things as well, including emissions, MPG, and reliability.
At 3000 RPM, for example, each crank deg is 55.55 usec. At 3000 RPM, an impulse (zero time width) injection at 30* BTDC, is followed by a 20* ignition delay, then a 5* delay as pressure rises to a maximum, so maximum occurs at 5* BTDC. The actual pulse width, PW, is about 555.5 usec, so that fuel is injected over a 10 deg interval of crank degs. Therefore, fuel injection occurs from 30* to 20* BTDC, then 10* to 0* BTDC for initiation of burn, and maximum pressure at 5* BTDC to 5* ATDC, and this gives maximum cylinder MEP and thus HP.
#50
04-06-2008, 05:02 PM
i see the resister has a brown stipe on one end..if i did this just like the pic...witch way does the brown stipe on the resister go??? or does it do its job ether way?? i know diods only work one way..im not great with electronics so please excuse so many questions...
It doesn't matter which direction you solder the resister. Current through them flows the same. The stripes on them indicate how much resistance they provide.
#52
04-06-2008, 05:22 PM
Originally Posted by ron's power stroke
All you need to do, is remove the original resistor, and solder in the correct resistor as listed
above for your model IDM. (Should be a sticker that lists the model near the connector).
In the pics I have, you would solder to the same place on the board that the green and yellow
wires are soldered. You shouldnt use wires or switches.
above for your model IDM. (Should be a sticker that lists the model near the connector).
In the pics I have, you would solder to the same place on the board that the green and yellow
wires are soldered. You shouldnt use wires or switches.
Ron. I just added some pics to my galley covering this very thing. Dave is on his way over here now, so by the end of the evening this gallery should be a fairly inclusive step by step how to....that's what I'm hoping for anyways.
2001 Ford F250 4x4 - IDM mod
#54
04-06-2008, 05:32 PM
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Ron. I just added some pics to my galley covering this very thing. Dave is on his way over here now, so by the end of the evening this gallery should be a fairly inclusive step by step how to....that's what I'm hoping for anyways.
2001 Ford F250 4x4 - IDM mod
2001 Ford F250 4x4 - IDM mod
whats this Gene is talking about?? i have a DP...
#55
04-06-2008, 05:48 PM
Originally Posted by ron's power stroke
whats this Gene is talking about??
IMO, seeing that we are likely talking about less than a millisecond difference, I don't know that it would be necessary to bother with it.....but your best bet would be to ask jody if he compensates for it or not.
#56
04-06-2008, 07:42 PM
Might I suggest a bulk purchase of both the resistors? I just priced five resistors delivered....$1.09 for the resistors, $5.00 handling, $2.32 postage for a total cost of $8.41 or $1.68 each.
I then priced 200 of the resistors...$16.68 for the resistors, $5.00 handling, $2.32 postage for a total cost of $24.00 or $0.12 each
EDIT: I just found out that the total cost to me would be almost exactly $40.00 (for 200 of each resistor)...no handling charges!!! So that makes them $0.10 each...5 mailed to you for $1.00, and that includes postage.
I'd be willing to do it if there is enough interest to make it worth our while...Any interest?
I then priced 200 of the resistors...$16.68 for the resistors, $5.00 handling, $2.32 postage for a total cost of $24.00 or $0.12 each
EDIT: I just found out that the total cost to me would be almost exactly $40.00 (for 200 of each resistor)...no handling charges!!! So that makes them $0.10 each...5 mailed to you for $1.00, and that includes postage.
I'd be willing to do it if there is enough interest to make it worth our while...Any interest?
#57
04-06-2008, 08:27 PM
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Might I suggest a bulk purchase of both the resistors? I just priced five resistors delivered....$1.09 for the resistors, $5.00 handling, $2.32 postage for a total cost of $8.41 or $1.68 each.
I then priced 200 of the resistors...$16.68 for the resistors, $5.00 handling, $2.32 postage for a total cost of $24.00 or $0.12 each
EDIT: I just found out that the total cost to me would be almost exactly $40.00 (for 200 of each resistor)...no handling charges!!! So that makes them $0.10 each...5 mailed to you for $1.00, and that includes postage.
I'd be willing to do it if there is enough interest to make it worth our while...Any interest?
I then priced 200 of the resistors...$16.68 for the resistors, $5.00 handling, $2.32 postage for a total cost of $24.00 or $0.12 each
EDIT: I just found out that the total cost to me would be almost exactly $40.00 (for 200 of each resistor)...no handling charges!!! So that makes them $0.10 each...5 mailed to you for $1.00, and that includes postage.
I'd be willing to do it if there is enough interest to make it worth our while...Any interest?
#59
04-07-2008, 09:11 AM
#60
04-07-2008, 11:27 AM
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