The Ultimate PoMoFo project begins...

[red95gts]

It doesn't get much more "PoMoFo" than building your own stand-alone Engine Control system..... :)

Parts have arrived and wanted to post some pictures. I'll keep this thread updated with my progress.

The product is call "Mega Squirt" and it's a DIY stand-alone ECU system with A LOT of capabilities. Firmware/Software is all open source code and people are constantly modifying and sharing with the public. What started out as a fuel-only system has evolved to include ignition control, boost control, shift light, and much more.

In addition to the ECU itself, I bought a "Stimulator" kit which allows for simulation of inputs in order to bench-test the system as well as communication to the laptop. I also purchased a "Relay Board" kit, which simplfies wiring and provides a neat package to mount fuel pump relays and the like. Also provides circuit protection for the ECU itself in case of a wiring fault.

Current cash outlay is $257 shipped for all three kits. I still need to order (from a different source) the parts to make a injector driver circuit capable of running 8 low-impedance injectors. That, however, should be right around $20 shipped. After building a completely new engine harness and a few simple stand-alone circuits, I plan on being in for less than $350 TOTAL for this project.

This system is Speed-Density based, so I won't need to buy a MAF. It alaso spares me from shelling out $$$ for:

low impedance injector driver
boost controller
shift light
2-step

All it'll take is a little (ok..maybe a lot! LOL) time on my part.... More to follow! I hope to have all of the hard parts built by next weekend. The wiring harness will be the real time-consuming part, I'm afraid....

The ECU Kit:

http://www.shawus.com/djermain/MegaSquirt/DSC05824.jpg

The ECU main board:

http://www.shawus.com/djermain/MegaSquirt/DSC05825.jpg



The Stimulator Kit:

http://www.shawus.com/djermain/MegaSquirt/DSC05823.jpg

The Relay Board Kit:

http://www.shawus.com/djermain/MegaSquirt/DSC05822.jpg

[Bubstang]

Thats looks kinda fun. Keep us posted on the progress.

Bubba

[maveRick]

You're smfart.

I dunno what all you just said, D, but it sounded useful and frugal. Put me down for one. I'll pick it up tomorrow evening. :D


Best o' luck on your project.

[HoustonLX]

Thats looks kinda fun.


The hell it does! Looks like a nightmare. :nuts:

[Otis!]

Looks like a good approach, and one attainable by someone with a fair amount of skill and patience...

Once you get it all done, please submit a labor quote to me and Mr. Book... :D

Cool deal D!

O!

Added Q: Do you have a link to a site D? Miht come in handy for future reference stuff, you know...

[Alex in Houston]

Funny, I've been looking at the MS.
What are you going to do for the TFI? I've gathered enough info that it seems like it won't need much. Looks like you can just run the PIP to MS board and run the tach out to a CD box (Crane, MSD). I found the info about the inverter board that wiull be needed on this page http://users.adelphia.net/~jimmble/index/TFI_mods.html
Only thing I haven't found info on is how it controls the timing advance (since you're only using the PIP from the distributor to the computer).
As far as the resistor box, I have been using a pair I got from Mitsubiushi Eclipse's for years. You can also find them on just about every Honda produced. Volvo and Toyota turbo models have them also. I added a pair of Molex connectors to the factory harness that allows me to plug/unplug the resistor harness if I need to switch to/from low Z/high Z injectors.

[red95gts]

Looks like a good approach, and one attainable by someone with a fair amount of skill and patience...

Once you get it all done, please submit a labor quote to me and Mr. Book... :D

Cool deal D!

O!

Added Q: Do you have a link to a site D? Miht come in handy for future reference stuff, you know...

www.msefi.com is the forums for the MS....there are links there to just about everything!

[red95gts]

Funny, I've been looking at the MS.
What are you going to do for the TFI? I've gathered enough info that it seems like it won't need much. Looks like you can just run the PIP to MS board and run the tach out to a CD box (Crane, MSD). I found the info about the inverter board that wiull be needed on this page http://users.adelphia.net/~jimmble/index/TFI_mods.html
Only thing I haven't found info on is how it controls the timing advance (since you're only using the PIP from the distributor to the computer).
As far as the resistor box, I have been using a pair I got from Mitsubiushi Eclipse's for years. You can also find them on just about every Honda produced. Volvo and Toyota turbo models have them also. I added a pair of Molex connectors to the factory harness that allows me to plug/unplug the resistor harness if I need to switch to/from low Z/high Z injectors.

It's my understanding that the circuit you linked to above is only needed to condition the output to go BACK to the TFI (and then drive the coil). If you run straight from the MS to a CD ignition, that circuit is not necessary. Now, the downside with that, is there is no easy way to disable advance (like a SPOUT jumper plug that we're all used to) to set base timing, but I'm working on a fix for that one... But, the upside is completely getting rid of the failure-prone TFI module...

The 94-95 cars have a remote mount TFI and the distributor sends out TWO PIP signals...one direct to the EEC and the other to the TFI. I'm a little concerned about signal amplitude with this setup though. If you believe what you read, we are only talking 0.4 volts peak-to-peak on the incoming PIP signal (direct off the hall effect sensor). I plan on putting a scope on my car and seeing what we've really got straight out of the distributor... May have to build a amplifier circuit to get the signal amp up a bit..

The modification for the injectors isn't a resistor box. They call it the "Flyback board" and it's basically a rugged injector driver with a big ass heat sink on it. The standard MS will do peak-and-hold injector signals, but the heat through the drivers kills them in short order. The flyback board basically transfers driving duties over to something that can handle the heat..

Once I get it built, you'd be more than welcome to come over and have a look!

D!

[red95gts]

Funny, I've been looking at the MS.
What are you going to do for the TFI? I've gathered enough info that it seems like it won't need much. Looks like you can just run the PIP to MS board and run the tach out to a CD box (Crane, MSD). I found the info about the inverter board that wiull be needed on this page http://users.adelphia.net/~jimmble/index/TFI_mods.html
Only thing I haven't found info on is how it controls the timing advance (since you're only using the PIP from the distributor to the computer).
As far as the resistor box, I have been using a pair I got from Mitsubiushi Eclipse's for years. You can also find them on just about every Honda produced. Volvo and Toyota turbo models have them also. I added a pair of Molex connectors to the factory harness that allows me to plug/unplug the resistor harness if I need to switch to/from low Z/high Z injectors.

After looking at the link a little closer, keep in mind the TFI wiring he is using is different than the remote-mount TFI. It has two power inputs (one for start and one for run) and the IDM signal is pulled straight off the "Coil -" signal with a resistor.

The remote-mount only has one power feed that is hot in run AND start. IDM is it's own seperate pin off the connector...

[Alex in Houston]

It's my understanding that the circuit you linked to above is only needed to condition the output to go BACK to the TFI (and then drive the coil). If you run straight from the MS to a CD ignition, that circuit is not necessary. Now, the downside with that, is there is no easy way to disable advance (like a SPOUT jumper plug that we're all used to) to set base timing, but I'm working on a fix for that one... But, the upside is completely getting rid of the failure-prone TFI module...

Actually I wasn't sure if that was needed or not (just learned something). I for one, may just use it and keep the TFI. I've only had one TFI ever fail on me and I've owned TFI equipped vehicles for 15 years.


Thee 94-95 cars have a remote mount TFI and the distributor sends out TWO PIP signals...one direct to the EEC and the other to the TFI.

Well it's just really a tap of the wire. The TFI plug is wired exactly the same as the one mounted on the distributor. Ford just spliced in a wire to feed both the computer and the TFI.


I'm a little concerned about signal amplitude with this setup though. If you believe what you read, we are only talking 0.4 volts peak-to-peak on the incoming PIP signal (direct off the hall effect sensor). I plan on putting a scope on my car and seeing what we've really got straight out of the distributor... May have to build a amplifier circuit to get the signal amp up a bit..

Damn you have an oscilliscope :hail:
I doubt you'll have to build an amplifier for the signal though. Ford puts the TFI in the front bumper on Cougars/thundebirds with a 3.8/5.0 and it has tons of wire length between it. The most they do is just wrap the TFI wires in aluminum foil with a shield ground, LOL but it seems to work.


The modification for the injectors isn't a resistor box. They call it the "Flyback board" and it's basically a rugged injector driver with a big ass heat sink on it. The standard MS will do peak-and-hold injector signals, but the heat through the drivers kills them in short order. The flyback board basically transfers driving duties over to something that can handle the heat..

Oh yeah, I've looked over the MS for a while now. I just find the resistor box easier and just as effective for much of anything up to a 60# injector.


Once I get it built, you'd be more than welcome to come over and have a look!

D!

Bet you don't have to ask me twice!! I'll definitely take you on the offer Darryl

[bigwhit]

hey Darrel, WHATS UP. I EMAILED YOU ABOUT 2 MONTHS AGO. KEEP IN TOUCH. AKHARDW@ATT.NET

[red95gts]

Damn you have an oscilliscope :hail:
I doubt you'll have to build an amplifier for the signal though. Ford puts the TFI in the front bumper on Cougars/thundebirds with a 3.8/5.0 and it has tons of wire length between it. The most they do is just wrap the TFI wires in aluminum foil with a shield ground, LOL but it seems to work.

Bet you don't have to ask me twice!! I'll definitely take you on the offer Darryl

Yeah, A digital Oscilliscope at that! :) Even stores waveforms to floppy disk... LOL

What I'd love to do is see what the output of the 94-95 "sealed" distributor is as compared to a distributor-mounted TFI. From the few vague schematics I've seen, it looks as though the PIP signal is amplified before leaving the TFI module (on the dist-mount variety, obviously). This will definitely change the resistors at the input to the MS....

I'll keep this thread posted!!

[red95gts]

hey Darrel, WHATS UP. I EMAILED YOU ABOUT 2 MONTHS AGO. KEEP IN TOUCH. AKHARDW@ATT.NET

Hey Whitney! How ya been? Got any times/dyno numbers/anything on the 347?? The suspense is killing me, dude!! :)

Hope things are going well for ya!

[red95gts]

Made some progress this weekend! Got everything assembled and working (on the bench at least). Still need to create a wiring harness that will include everything I need and integrate a wideband 02.

Overall the kit was VERY well marked and, although time-consuming, pretty easy to put together. The case took a little head-scratching to figure out, but nothing too serious... :)

This thing is in DIRE need of a PMFR sticker! :)

Here is the MegaSquirt and the Stimulator plugged into the DB37 connector. The Stimulator simulates TPS, IAT, CLT, O2, and RPM in order to bench-test most of the MS functions. Once the MS is installed, the wiring harness replaces the stimulator and we have actual, real inputs and outputs.

http://www.shawus.com/djermain/MegaSquirt/DSC05884.jpg

This is a close up of the Stimulator. Although they claim this is an "optional" item, it's HIGHLY recommended since you use it at several key steps in the MS build to check your progress.

http://www.shawus.com/djermain/MegaSquirt/DSC05886.jpg

This is the end of the MS where you plug in the laptop with a standard Serial cable for logging, programming changes, and firmware re-flashes. The leftmost LED blinks anytime an injector driver is on. The middle LED comes on when the system is in fuel enrichment mode (i.e. Coolant Temp is below a specified point). The last LED is for Accel Enrichment mode (i.e. when the TPS signal rises beyond a certain counts/sec, it adds more fuel). AKA an Accelerator Pump to you carb guys.. :)

http://www.shawus.com/djermain/MegaSquirt/DSC05888.jpg

This is the DB37 end that will eventually plug into the custom wiring harness. Notice the barb fitting for the on-board MAP sensor.

http://www.shawus.com/djermain/MegaSquirt/DSC05889.jpg

This is a screen-shot (of sorts) of the basic "Mega-Tune" software. Since I took this picture earlier, I have updated the software and firmware to MSnS-E, which allows fuel and spark control and well as many, many extras, but this gives you a basic idea as to the user interface.

http://www.shawus.com/djermain/MegaSquirt/DSC05891.jpg

This has been a very fun project so far and I can't wait to get this thing installed on the car and see how it works!

More to follow!

Edit - Forgot to keep the cost total running. Had to buy solder and a lead-bending tool last week. Total cost is now $261.

[TRAXX]

Very cool D! One of these days ill read what you typed...but for now I just looked at it Nudie magazine style :smokin:

[gt350mustang]

cool!!!!!!!!!! they made it look like a coke can . very stealthy. now, what are you using to show scale? a radar detector? :):