EFI running from a PC?

[65ShelbyClone]

DIY PC EFI and EEC Voodoo back from the Dead!

I know this isnt actually 5.0 tech, but I figure most people here play with EFI and might benefit If I find something out.

Just some background:
I have a single cylinder turbo project engine I'm playing with and rather than try to do a blow or draw-through carb, I'd like to just fuel inject it for the tuning ability. For the time being, I just need the setup for testing on a stand so size and wiring is not an issue, but simplicity and budget are.

All I really need is something that can detect a crank position sensor, MAP sensor(or air meter), TPS, and fire an injector while varying the pulsewidth. Hell, it can even omit the PC and be analog.

Does anyone know if I could just use software and have a PC as the fuel conroller? Could I hook into an existing/retrofitted car ECU and use the PC as a piggyback? What about schematics for a simple analog controller?

Thanks

 

[jrichker]

My head is spinning the software alone would be a lifetime project for most of us...

 

[65ShelbyClone]

It couldnt be any worse than creating the firmware and tables for a standalone, could it?

What is used when an EFI engine is on a dyno? The ECU that will go in the car, or some dedicated dyno-room standalone?

I am also researching building a simple analog ECU using some kind of pulse width modulator. Now that I think about it, all it may need is input from a MAP sensor so it can widen the pulse AND compensate for throttle position.

 

[jrichker]

It couldnt be any worse than creating the firmware and tables for a standalone, could it?

What is used when an EFI engine is on a dyno? The ECU that will go in the car, or some dedicated dyno-room standalone?

I am also researching building a simple analog ECU using some kind of pulse width modulator. Now that I think about it, all it may need is input from a MAP sensor so it can widen the pulse AND compensate for throttle position.

The answer is to use the TPS output to run a VFO (variable frequency oscillator) More throttle = higher frequency. The VFO output feeds the clock input of a D flip-flop. The data input of the D flip flop is from a stang Baro sensor, that is connected to the intake manifold. The output of the D flip-flop feeds a one input of an AND gate. The other input of the AND gate is fed by a pickup circuit that detects the opening of the intake valve. The AND gate output feeds a driver that powers the injector. Now you have your Speed Density computer, very crude, but the theory will work.

 

[65ShelbyClone]

Thats all a great help. A few more questions, though;

What is the injector driver? Is just a solid state relay triggered by the flip-flop? Also, how would my low-impedance injectors factor in? I have some from a turbo 2.3.

Can something this rudimentary be adjusted and "tuned?" I really doubt it will even run without alot of trial and error.

Last, could it be set up to richen the mixture under boost with a positive pressure MAP?

 

[jrichker]

Thats all a great help. A few more questions, though;

What is the injector driver? Is just a solid state relay triggered by the flip-flop? Also, how would my low-impedance injectors factor in? I have some from a turbo 2.3.

Can something this rudimentary be adjusted and "tuned?" I really doubt it will even run without alot of trial and error.

Last, could it be set up to richen the mixture under boost with a positive pressure MAP?

Getting the base A/F ratio set correctly would require a lot of trial & error, not a good plan.

 

[jackchan]

i often wondered if there would possibly be a way to put a home pc in an automobile. I mean, it's all converted to 12v anyways, after it leaves the power suppply.

instead of a lap top why not incorperate a moniter in the dash or in front of the dash and run all the power cables etc to the trunk area or back seat area if the back seat were eliminated .......that way you could build a speaker enclosure, to mount the "tower" in.
Since some companys have lap top data logging anyways, I dont see why a cheap CPU etc couldnt be used in this application and it be basically onboard live dianostics?
keep this thead going.......this is very interesting!
Jack

 

[65ShelbyClone]

You know, I actually found an old Yahoo! group thats goal was to make an Intel motherboard into an EFI controller. Unfortunately, it never gained many members and went belly-up back in '02 without any progress. If I was an electronics/software engineer, I'd just start building the hardware and software myself.

My original plan was to use a turbo 2.3 ecu and the bare minimum of sensors. Its already batch fire, so using one or two injectors isnt as fussy. It would be a huge bonus to find some OEM computer that needs the least mods to make flashable. Anyone know of a possible candidate?

After giving it some more thought, the logic runs backwards. It would shorten the injector dwell time rather than lengthen it.

So the increasing voltage that comes from the MAP sensor would make the duty cycle shorter?

 

[Repostyle]

I was just about to start a new thread about almost this same thing. Then I saw this one and figure I'll just piggy back on it since it's basically the same topic with different goals.

Anybody know where I can find some software and hardware for tuning my stang from my laptop? All I can find is stuff for OBD II cars, and our cars are ECU cars, right? I found a really cool program for OBD II http://www.digimoto.com which does everything I want from tuning to Dyno results, but it's not compatible with our older cars.

 

[65ShelbyClone]

I was just about to start a new thread about almost this same thing. Then I saw this one and figure I'll just piggy back on it since it's basically the same topic with different goals.

Anybody know where I can find some software and hardware for tuning my stang from my laptop?

Hopefully we'll both get closer to a solution through this thread. However, what you want to do has been covered already in this forum. Search for "Megasquirt" or "twEECer." Megasquirt is a standalone computer and the twEECer works on EEC-IV Fords(OBD1).

I made a little more progress today, but only a little. I stumbled on the diy-efi.org site and mailing list. They even had an FTP area with schematics and downloads for running an engine through the parallel port on a PC. Unfortunately a server crash that happened who know when wiped out all that valuable info and nobody has fixed it.

 

[jackchan]

http://www.fordfuelinjection.com/

this site will give you a lot of EFI info. I still am wanting at least EEC-IV chip burning capability so I can burn my own chips. Auto logic is nearly non existant.......you cant find mike wesley with a medal detector....these days!
And no one else wants to fool with older EEC-IV computers it seems. I wish someone would come out with a windows based chip burning program for at least the EEC-IV.
thanks
Jack

 

[jrichker]

http://www.fordfuelinjection.com/

this site will give you a lot of EFI info. I still am wanting at least EEC-IV chip burning capability so I can burn my own chips. Auto logic is nearly non existant.......you cant find mike wesley with a medal detector....these days!
And no one else wants to fool with older EEC-IV computers it seems. I wish someone would come out with a windows based chip burning program for at least the EEC-IV.
thanks
Jack

You can download the contents of a Tweecer bin file to you PC. Spend $200 and you can buy an Eprom burner for your Windows PC. Remove the EEC from your car and find a good electronics tech to remove the control prom and solder a ZIF socket in the place where the prom was. Then you can install the prom you created on your prom burner from the modified Tweecer bin file. Put the EEC back in the car and go. Not hard at all if you have some good electronics/PC skills .

 

[65ShelbyClone]

Well, I suppose all you would need is a few EEPROMS, a socket that can be plugged into your computer, and a software program capable of editing the relevant data. Thats all the chip programmers do after charging $100+.

EDIT: oops, beat me.

 

[795.0pacecar]

What about using the fuel injection system that is used on many single cylinder ATVs and dirt bikes?

 

[HISSIN50]

Well it would be nice y'all shared your smart thoughts with us stupid people more often. The other day when Jrichker first told me about the DIY Eprom chip burn, it sounded like magic.

FWIW, the EEC Analyzer software might be helpful for some fine tuning with this Eprom stuff. Seems to me that the TwEECer folks use it. I do think there is a [one time?] fee to use it though.

 

[65ShelbyClone]

What about using the fuel injection system that is used on many single cylinder ATVs and dirt bikes?

That was my first choice, actually. Ideally I would just transplant the whole system from one onto my test engine, but I figure it would be alot more difficult to track one down. Tuning and retrofitting may be easier, but components harder to find. I can only think of a handful of single cylinders that have it. I'd be thrilled if I can do this for less than $50.

The other day when Jrichker first told me about the DIY Eprom chip burn, it sounded like magic.

What? When? Where can I find it?

Some more stuff I found out today while I was shut in the house waiting for the rain to stop: I have another relatively cheap option by using a '92-95 Honda Civic or Integra ECU and the Uberdata chipping kit and software(two chips and some capacitors for ~$15). The problem is that you need an EPROM programmer to write the chip, which seems to be a minimum of $50. I found some for less on Ebay, though.

I actually have two 28 pin EPROMS from about 25 years ago. No idea what kind, except one is Mitsubishi.

Something else that came to mind going back to the PC control is hooking to ECU like a twEECer through the J3 port.

 

[HISSIN50]

What? When? Where can I find it?

First off, let me say that I dont pretend to have a clue about all this computer stuff. I do pretty well with larger (what I call Macro) circuits, wiring and what-not. But when it comes to computer boards, chips (micro systems, using my terminology) and all this little stuff that you guys are talking about, smoke comes out of my ears and I start to drool.

Here is a link to the thread where Jrichker gave some basic info and first got my wheels turning. I think what he posted above in your thread mirrors what he mentioned on the other thread. But honestly, I really have no idea what he is talking about (as you can see from my later post after he provided the info) so I need to research stuff quite a bit just to know what and how all this stuff works and interacts.
65SC, it sure seems that you already have a very good knowledge of this stuff so I know I wont be able to offer anything helpful unfortunately.
But do keep the thread updated because though I dont understand this stuff, I find it kind of intriguing (it is like magic to me).

 

[65ShelbyClone]

65SC, it sure seems that you already have a very good knowledge of this stuff so I know I wont be able to offer anything helpful unfortunately.
.

Dont be fooled, I have little more than a basic knowledge of electronic circuits, let alone digital systems. About 50% of what I know I have learned in the last 36 hours. Anything you can contribute is helpful. I didnt know that a socket could be installed in a factory ECU until you showed me that thread. I may get an EPROM programmer just to have one since they can be so useful.

I may go out tomorrow and see what kind of cheap ECUs I can scrounge up. Possibilities are from an early '90s Nissan 240SX and Sentra, but I think they need an extra board installed for tweaking.

 

[jackchan]

You can download the contents of a Tweecer bin file to you PC. Spend $200 and you can buy an Eprom burner for your Windows PC. Remove the EEC from your car and find a good electronics tech to remove the control prom and solder a ZIF socket in the place where the prom was. Then you can install the prom you created on your prom burner from the modified Tweecer bin file. Put the EEC back in the car and go. Not hard at all if you have some good electronics/PC skills .

I am a industrial instrumentation, electrical technician. We solder in resisters all the time........I'll buy whatever i need to buy to make this work...and
I have a spare A9L computer , and am more than willing to try this, I may however need some of your help. If we can pull this off........you have PM!

but I wonder, couldn't you put a ZIF socket in the service port....and do it that way?
thanks
Jack

 

[jackchan]

I also need a BIN file reader? anyone got any ideas on that one?
Jack