Flex Fuel with MegaSquirt Controller
#21
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Hmmmmm....
I decided against case-mounting on mine simply because I knew that the box was going to be opened and closed a million times as I experimented with it. I guess with Chris' unit this won't be an issue so I can just stick it on one of the endplates. And with the one spot we freed up by removing the 912 (which is truly useless in this application) I think that covers us for heatsink requirement.
BTW- I like the new insulators you guys are shipping with the TO-220 modkits, with the nylon shoulder washers and such. Much better than the old stuff.
I decided against case-mounting on mine simply because I knew that the box was going to be opened and closed a million times as I experimented with it. I guess with Chris' unit this won't be an issue so I can just stick it on one of the endplates. And with the one spot we freed up by removing the 912 (which is truly useless in this application) I think that covers us for heatsink requirement.
BTW- I like the new insulators you guys are shipping with the TO-220 modkits, with the nylon shoulder washers and such. Much better than the old stuff.
#23
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Today's episode of "What the hell was I thinking?" is brought to you by the fact that MS2 doesn't even support WI control to begin with. So that's kind of a non-issue now. Chris, your heatsink components and endplates are both safe. Buy a Devil's Own WI pump controller. ![](https://www.miataturbo.net/images/smilies/cool.gif)
Got the launch control / flatshift circuit and a pair of relay driver circuits built last night. Kept running into trouble as I was missing a few trivial parts (stuff I forgot to buy at Fry's on Wednesday) so today I've got what will hopefully be the final "needs to be purchased" list and we'll be able to finish up with everything else.
I was kinda surprised to see in the MS2E documentation that in order to do table-switching I've got to solder a wire onto one pin of the tiny little QFP48 microprocessor. Not a problem here in the lab (got a Metcal iron and a Leica stereomicroscope) but I can't imagine the average user doing this with a Radio Shack iron and a magnifying glass...
![](https://www.miataturbo.net/images/smilies/cool.gif)
Got the launch control / flatshift circuit and a pair of relay driver circuits built last night. Kept running into trouble as I was missing a few trivial parts (stuff I forgot to buy at Fry's on Wednesday) so today I've got what will hopefully be the final "needs to be purchased" list and we'll be able to finish up with everything else.
I was kinda surprised to see in the MS2E documentation that in order to do table-switching I've got to solder a wire onto one pin of the tiny little QFP48 microprocessor. Not a problem here in the lab (got a Metcal iron and a Leica stereomicroscope) but I can't imagine the average user doing this with a Radio Shack iron and a magnifying glass...
#24
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Today's episode of "What the hell was I thinking?" is brought to you by the fact that MS2 doesn't even support WI control to begin with. So that's kind of a non-issue now. Chris, your heatsink components and endplates are both safe. Buy a Devil's Own WI pump controller. ![](https://www.miataturbo.net/images/smilies/cool.gif)
![](https://www.miataturbo.net/images/smilies/cool.gif)
Got the launch control / flatshift circuit and a pair of relay driver circuits built last night. Kept running into trouble as I was missing a few trivial parts (stuff I forgot to buy at Fry's on Wednesday) so today I've got what will hopefully be the final "needs to be purchased" list and we'll be able to finish up with everything else.
I was kinda surprised to see in the MS2E documentation that in order to do table-switching I've got to solder a wire onto one pin of the tiny little QFP48 microprocessor. Not a problem here in the lab (got a Metcal iron and a Leica stereomicroscope) but I can't imagine the average user doing this with a Radio Shack iron and a magnifying glass...
#25
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Nah, I haven't really been keeping track, it's probably under $20- don't sweat it.
Got all the hardware mods finished tonight. I haven't exhaustively tested all the ancillary I/O yet, but the basics (fuel, spark, WBO2, etc) all seem to be working. A tip of the hat to the folks at DIYAutotune.com who did the principal assembly of the basic 3.0 board- a very clean job of it.
One thing I gotta say- a lot of folks bitch that the MS1 software seems confused and uncoordinated, well, the MS2 software is downright sociopathic. I'm still trying to figure out why the left-hand column in the VE and Spark tables is labeled in % rather than KPa, and scaled only from 0 to 100... Anybody have a clue on this? 'Cuz I'm stumped. I've set Speed Density in every space I can find.
Anyway, pictures. It's not my most beautiful wiring job ever, but it seems to be solid. I did the mods on the MS2 daughterboard to run down unused pins of the DIP-40 and then get picked up again on the other side, so you don't have to worry about wires dangling from the CPU to the mainboard.
![](http://img295.imageshack.us/img295/4034/chrisfrontys7.jpg)
![](http://img295.imageshack.us/img295/3246/chrisbackoj5.jpg)
I've built the following functions onto your board:
1- Relay driver for fan (closure to ground).
2- Relay driver for misc (closure to ground).
3- Input for table switching (active-low).
4- Input for launch / flatshift (active-low).
5- Constant barometric correction.
6- Input for knock (for KnockSenseMS).
7- Input for Flex Fuel.
Full documentation on the mods (pin assignment, etc) will follow. Still haven't started on the harness, though that should be easier now that all the I/O is, if you'll pardon the pun, pinned down.
Got all the hardware mods finished tonight. I haven't exhaustively tested all the ancillary I/O yet, but the basics (fuel, spark, WBO2, etc) all seem to be working. A tip of the hat to the folks at DIYAutotune.com who did the principal assembly of the basic 3.0 board- a very clean job of it.
One thing I gotta say- a lot of folks bitch that the MS1 software seems confused and uncoordinated, well, the MS2 software is downright sociopathic. I'm still trying to figure out why the left-hand column in the VE and Spark tables is labeled in % rather than KPa, and scaled only from 0 to 100... Anybody have a clue on this? 'Cuz I'm stumped. I've set Speed Density in every space I can find.
Anyway, pictures. It's not my most beautiful wiring job ever, but it seems to be solid. I did the mods on the MS2 daughterboard to run down unused pins of the DIP-40 and then get picked up again on the other side, so you don't have to worry about wires dangling from the CPU to the mainboard.
![](http://img295.imageshack.us/img295/4034/chrisfrontys7.jpg)
![](http://img295.imageshack.us/img295/3246/chrisbackoj5.jpg)
I've built the following functions onto your board:
1- Relay driver for fan (closure to ground).
2- Relay driver for misc (closure to ground).
3- Input for table switching (active-low).
4- Input for launch / flatshift (active-low).
5- Constant barometric correction.
6- Input for knock (for KnockSenseMS).
7- Input for Flex Fuel.
Full documentation on the mods (pin assignment, etc) will follow. Still haven't started on the harness, though that should be easier now that all the I/O is, if you'll pardon the pun, pinned down.
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Pictures like that certainly keep me humble. Thanks for the hard work.
Now, do you want the good news first or the bad???
Good news, the Old Chub has arrived safely in San Diego...
The bad news... There were only two six packs available for purchase in Colorado Springs.
Now, do you want the good news first or the bad???
Good news, the Old Chub has arrived safely in San Diego...
The bad news... There were only two six packs available for purchase in Colorado Springs.
#27
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More good news.
All I/O have now been tested and are operating. The only one I haven't checked out is the FlexFuel input, as I have no way of simulating that signal at the moment. We've got a fancy function generator at work that I'm going to borrow, and hopefully I can produce a signal with that which reasonably approximates what the MS is looking for. I've never actually seen a FlexFuel sensor in real life, so it'll be an educated guess.
Now, onto the boring part: building the damn harness... You friggin' Plug-n-Play people...
All I/O have now been tested and are operating. The only one I haven't checked out is the FlexFuel input, as I have no way of simulating that signal at the moment. We've got a fancy function generator at work that I'm going to borrow, and hopefully I can produce a signal with that which reasonably approximates what the MS is looking for. I've never actually seen a FlexFuel sensor in real life, so it'll be an educated guess.
Now, onto the boring part: building the damn harness... You friggin' Plug-n-Play people...
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#28
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More good news.
All I/O have now been tested and are operating. The only one I haven't checked out is the FlexFuel input, as I have no way of simulating that signal at the moment. We've got a fancy function generator at work that I'm going to borrow, and hopefully I can produce a signal with that which reasonably approximates what the MS is looking for. I've never actually seen a FlexFuel sensor in real life, so it'll be an educated guess.
All I/O have now been tested and are operating. The only one I haven't checked out is the FlexFuel input, as I have no way of simulating that signal at the moment. We've got a fancy function generator at work that I'm going to borrow, and hopefully I can produce a signal with that which reasonably approximates what the MS is looking for. I've never actually seen a FlexFuel sensor in real life, so it'll be an educated guess.
In the words of Harry Callahan (Magnum Force 1973) "A man has got to know his limitations..."
#29
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Man, I hate harness-building... Easy, but tedious...
![](http://img37.picoodle.com/img/img37/4/7/25/thraddax/f_Harnessm_43b8c51.jpg)
When you get this, you'll gain an appreciation for my perspective regarding grounds. When building an MS, it's important to have enough ground wires. Too many is enough.
Three to the main connector, and two more are those two black wires. I suggest you pre-run a pair of heavy wires through the firewall to a new ring connector on the head for these to connect to.
Also- what's the status on the connector for your IAC and TPS? I've wired this to use your stock TPS wires, but you're going to need to cut off the stock 3-wire plug and install an NB 4-wire plug. Start hitting the junkyard now, I'll provide instructions to follow.
![](http://img37.picoodle.com/img/img37/4/7/25/thraddax/f_Harnessm_43b8c51.jpg)
When you get this, you'll gain an appreciation for my perspective regarding grounds. When building an MS, it's important to have enough ground wires. Too many is enough.
Three to the main connector, and two more are those two black wires. I suggest you pre-run a pair of heavy wires through the firewall to a new ring connector on the head for these to connect to.
Also- what's the status on the connector for your IAC and TPS? I've wired this to use your stock TPS wires, but you're going to need to cut off the stock 3-wire plug and install an NB 4-wire plug. Start hitting the junkyard now, I'll provide instructions to follow.
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The harness looks great. The TPS plug is already taken care of, although I ran a wire outside the stock harness to carry the variable signal. I will start looking for the IAC plug, but if I can't find one, I can probably get the one from the "donor" car. I haven't cut the harness on it, and am trying to avoid doing so.
I can suffer with a poor idle until warm with no ill effects until I secure one right?
(How was the beer?)
I can suffer with a poor idle until warm with no ill effects until I secure one right?
(How was the beer?)
#31
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Mmmm. Beer good.
For TPS, you'll want to wire the new TPS plug into the factory harness as follows, assuming '99 colors on the TPS pigtail:
'99 light green / red to '92 red. (TPS Vref from pin 1N / pin 26)
'99 green / black to '92 light green / white (TPS sig, pin 2L / pin 22)
'99 black / red to '92 black / light green (GND)
Specifically, here's what your pinout looks like altogether:
For TPS, you'll want to wire the new TPS plug into the factory harness as follows, assuming '99 colors on the TPS pigtail:
'99 light green / red to '92 red. (TPS Vref from pin 1N / pin 26)
'99 green / black to '92 light green / white (TPS sig, pin 2L / pin 22)
'99 black / red to '92 black / light green (GND)
Specifically, here's what your pinout looks like altogether:
![](http://img32.picoodle.com/img/img32/4/7/28/thraddax/f_ChrisMS2Pinm_be1cd74.gif)
#32
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you guys frighten me you know too much ive been considering doing e85 conversion over here in uk on my 1999/10AE only you seem to go through alot of trouble other than paying someone else to do it is there a simpler way? alot of bio sites just want to sell me/you/anyone plugin piggy back ecu's plus wires and i know on my older car i have to change alot of seals pumps etc.. but you seem to have alot of trouble or am i missing something? sorry new to almost all modding and havnt even supercharged mine yet.
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#33
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you guys frighten me you know too much ive been considering doing e85 conversion over here in uk on my 1999/10AE only you seem to go through alot of trouble other than paying someone else to do it is there a simpler way? alot of bio sites just want to sell me/you/anyone plugin piggy back ecu's plus wires and i know on my older car i have to change alot of seals pumps etc.. but you seem to have alot of trouble or am i missing something? sorry new to almost all modding and havnt even supercharged mine yet.![eek5](https://www.miataturbo.net/images/smilies/eek5.gif)
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Seals and stuff do need to be replaced, but mostly you just need to re-tune your VE table for E85.
#34
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Indeed. To do a straight E85 conversion, I believe you'd simply need to install larger injectors. Flex Fuel is where the complexity comes in- the ability for the system to automatically detect what type of fuel you are running and adjust accordingly, without user intervention.
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One has nothing at all to do with the other. You can run COP with pretty much any ECU, on any fuel. So yes, after having converted the fuel delivery and engine control systems for flex fuel operation, doing a COP conversion will work just as well as if you were still running normal petrol.
If you ask good questions, around here you'll get good answers.
If you ask good questions, around here you'll get good answers.
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#38
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Back from the dead.
Joe,
Can you tell from the pictures if I can run low impedence injectors? I can't tell for sure from reading the thread whether or not we deleted that capability.
Also, is sequential injection possible? What all would YOU have to build on my setup to make it happen?
--Chris
I found a post where Joe already answered the question, I can run low-z
Joe,
Can you tell from the pictures if I can run low impedence injectors? I can't tell for sure from reading the thread whether or not we deleted that capability.
Also, is sequential injection possible? What all would YOU have to build on my setup to make it happen?
--Chris
I found a post where Joe already answered the question, I can run low-z
Last edited by Chris Swearingen; 01-08-2010 at 01:00 PM. Reason: It sucks to be old and have no memory
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I can answer that, Low impedance injectors yes.
Sequential requires an additional 2 injector drivers, either two copies of your current circuits or 4 new ones via JBPerfs injectors&ignition driver card.
To keep low impedance injectors with sequential you'll also need his peak and hold driver card if you use his injectors&ignition driver card
Sequential requires an additional 2 injector drivers, either two copies of your current circuits or 4 new ones via JBPerfs injectors&ignition driver card.
To keep low impedance injectors with sequential you'll also need his peak and hold driver card if you use his injectors&ignition driver card
#40
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Okay, I think I have mentioned on this forum before that my electrical knowledge begins and ends with "Don't let the magic white smoke out".
I went to the jbperf site, saw the boards and some directions with squiggly lines and colors and came back here with questions.
Question one: Is there a way to utilize the sequential ignition and injection driver card without owning a soldering iron?
Question two: Do I need to be reading the Crank trigger wheel as well as the CAS to know when to inject? ( I have a '99 four tooth wheel on the car, but the sensor is in a parts box somewhere)
Question three: If I go full sequential on the injection, will my current injectors be big enough? I currently squirt twice per cycle right? So full sequential gives me greater control but less capacity?
I went to the jbperf site, saw the boards and some directions with squiggly lines and colors and came back here with questions.
Question one: Is there a way to utilize the sequential ignition and injection driver card without owning a soldering iron?
Question two: Do I need to be reading the Crank trigger wheel as well as the CAS to know when to inject? ( I have a '99 four tooth wheel on the car, but the sensor is in a parts box somewhere)
Question three: If I go full sequential on the injection, will my current injectors be big enough? I currently squirt twice per cycle right? So full sequential gives me greater control but less capacity?