Digital ECU Project

wallywest

Low Mileage
1. Plug and play - meaning a simple unit swap with no additional bits or cable changes.
2, Programmable engine parameters.
3. Diagnostics - data output to a laptop or I pad etc.
I've made some progress on prototype software and hardware interfaces but I need help with
1. A dead or no longer wanted ECU - I just need the connector but the housing would be a bonus.
2. Suggestions for features/ideas/comments.
3. Any expression of interest in what I am doing.
I have spent less than $100 so far but it will soon be time to commission a printed circuit board and that will probably cost a few hundred-maybe quite a few.
I considered trying crowd funding but now I'm wondering about "group of fanatic masochists" funding. Is anyone interested in throwing a few bucks into the pot with the possibility of a workable unit at the end?
Why do I think I can do this?
1. I am an Electrical Engineer by profession. I've done hardware and software product design.
2. I've been an amateur mechanic for more than 40 years (yikes!)
3. Functionally the analog ECU is pretty simple. I've investigated and found solutions for the hurdles I've identified so far.
4. I'm stubborn.

If anyone is interested please let me know. I am willing to provide status reports as I move along.

Thanks for listening.

wally.occomore@gmail.com
 
Interesting project. I work in the electronics industry and my be able to help out. I am also in Ontario.

Brian
 
Definitely interested. But have you investigated the numerous existing programmable ECU's that will work for this? There are many already on the market, including at least one specifically marketed for the X1/9 application as a 'plug and play' kit. The benefit to yours would have to be lower selling point and/or better features. Both of which might be difficult to do, but I am hoping you can.
As for input, allow provisions for programming upgrades; turbos, nitrous oxide, performance head/exhaust/induction, etc.
Tell us more about your plans so far.
 
I have a very similar system. It’s a MegaSquirt ECU in the Bosch case. All the stock sensors and harness are used. The air flow meter is eliminated. Literally a one hour conversion.
 
Mark, what initial files did you use for programming the tune (base map) and where did you find it?
 
I got it from John Allen. I never ended up running it other than a couple times due to too many cars and projects.
 
I got it from John Allen. I never ended up running it other than a couple times due to too many cars and projects.

I had one of those systems as well - megasquirt in a stock ECU box that plugged into the stock wiring harness. I didn't get it directly from John, it passed through one or more owner before I got it, and I have since passed it on to another local member here. Pretty sure I still have the map files kicking around on my hard drive somewhere.

Pete
 
Some pics I found of the setup.

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Definitely interested. But have you investigated the numerous existing programmable ECU's that will work for this? There are many already on the market, including at least one specifically marketed for the X1/9 application as a 'plug and play' kit. The benefit to yours would have to be lower selling point and/or better features. Both of which might be difficult to do, but I am hoping you can.
As for input, allow provisions for programming upgrades; turbos, nitrous oxide, performance head/exhaust/induction, etc.
Tell us more about your plans so far.

The one marketed for our cars. . . are you referring to the $4k VAS kit?

I'd love to see this work out. I have bigger injectors waiting in my mailbox as we speak along with a throttle plate for a Megasquirt, but no point in installing them using stock computers.
 
are you referring to the $4k VAS kit?
Yes, hence my comment "The benefit to yours would have to be lower selling point and/or better features."

but no point in installing them using stock computers
Completely agree. There are a number of improvements available when converting to a aftermarket ECU, depending on the design of that ECU and what features are included. A real benefit here would be the second half of my earlier comment "better features".
 
Yes, hence my comment "The benefit to yours would have to be lower selling point and/or better features."


Completely agree. There are a number of improvements available when converting to a aftermarket ECU, depending on the design of that ECU and what features are included. A real benefit here would be the second half of my earlier comment "better features".


I figured as much, just wanted to make sure there wasn't another out there that I wasn't aware of. :D

I think the community would vastly encourage the idea of a reasonably priced ECU upgrade. I know I would.
 
1. Plug and play - meaning a simple unit swap with no additional bits or cable changes.
2, Programmable engine parameters.
3. Diagnostics - data output to a laptop or I pad etc.
I've made some progress on prototype software and hardware interfaces but I need help with
1. A dead or no longer wanted ECU - I just need the connector but the housing would be a bonus.
2. Suggestions for features/ideas/comments.
3. Any expression of interest in what I am doing.
I have spent less than $100 so far but it will soon be time to commission a printed circuit board and that will probably cost a few hundred-maybe quite a few.
I considered trying crowd funding but now I'm wondering about "group of fanatic masochists" funding. Is anyone interested in throwing a few bucks into the pot with the possibility of a workable unit at the end?
Why do I think I can do this?
1. I am an Electrical Engineer by profession. I've done hardware and software product design.
2. I've been an amateur mechanic for more than 40 years (yikes!)
3. Functionally the analog ECU is pretty simple. I've investigated and found solutions for the hurdles I've identified so far.
4. I'm stubborn.

If anyone is interested please let me know. I am willing to provide status reports as I move along.

Thanks for listening.

wally.occomore@gmail.com

If you want to do this because you want to and it would be fun then I whole heartedly support your endeavor. In fact, the Megasquirt project started this way. The current version of the MS system is very good and given its capability, support and cost I don't see the advantage of rolling your own. That is; (again) unless you just want to, or think you have a better idea for how the system would work.

I have been a user of programmable ECU's since 1991 when I put one on my '74 X1/9 autocross car.
 
What's in the tube providing air data? Hot wire or grid or something else?

Good question. Here is the line from the installation manual:


    • Install the AFM replacement tube
    Position the new plastic AFM replacement tube on the stock AFM mounting bracket with the air temperature sensor pointing up. Make sure the 2 metal spacers are in the rubber grommets when offering the mounting studs to the bracket. Slip on the rubber air tube to the throttle body and the rubber tube to the air filter; do not tighten the clamps yet.

So it just refers to it as an air temp sensor. As I recall it looked a lot like the ambient air temp sensor that mounts in the air filter box on my Ford/037 project.

I know very little about FI systems but I think that would make it a speed/density system?

Pete
 
I know very little about FI systems but I think that would make it a speed/density system?


Yes. The MS system can be configured as speed density so there is no need for an AFM. In fact, you can make one of these run with just; intake air temp, rpm pickup, coolant temp, TPS (throttle position sensor) and MAP (Manifold Absolute Pressure - vacuum).
 
I met John Allen several years ago at one of Wayne's get together's near Centralia, Wa. I am pretty sure that the tube measures intake air temp as well as has a MAP (manifold absolute pressure) sensor to measure air pressure, instead of air flow like the flap AFM. When you step on the gas, the butterfly in the manifold opens, air pressure drops immediately which the MAP sensor detects much faster than the flap does. It sends the signal to the ECU to control the fuel delivery.
 
"The current version of the MS system is very good and given its capability, support and cost I don't see the advantage of rolling your own." -@Steve

By currently version, are you referring to what Megasquirt offers off the shelf today?

I think I need to do a little more reading on Megasquirting these cars. Not sure I fully understand exactly what components need to be altered in order for installation. I'm also seeing prices around $1200 just for the units. Is that a fair price for the results you can obtain from adding it to our cars?

Having troubles properly quoting just that one line on my phone .
 
Its actually very simple.

You need:

A MAP (Manifold Absolute Pressure Sensor - 1 bar), mounted in the intake plenum down stream from the throttle plate. It cannot be mounted in the intake feed upstream from the throttle plate because it couldn't read vacuum with the plate closed.

TPS (true tps not just a switch like the L-Jet uses),

RPM sensor (I was able to use he trigger in the factory distributor but a trigger that reads the cam pulley works nicely)

Coolant Temperature (mounted in the head like the L-jet unit is.

Intake Air Temp Sensor (mounted in the feed to the throttle plate).

MS ECU and wiring harness. You could use the factory harness and replace the ECU connector. For me its easier to simply buy the generic harness with the ECU.

In fact, because the SOHC engine doesn't have any of the fancy stuff like variable valve timing, you could use a Micro Squirt system instead of the Mega Squirt system. The MicroSquirt is a simpler and cheaper version of the Mega Squirt and would work just fine on the X1/9 SOHC motor. The MicroSquirt system sells for $388 with the harness.

https://www.diyautotune.com/product/microsquirt-engine-management-system-w-8-39-wiring-harness/

I am sure that this system could squeeze a few extra ponies from the mostly stock motor. But what makes it such a value is it would make for easy tuning of simple performance mods; Ported intake and head, more aggressive camshaft, exhaust, increased compression, etc...

Its easy to install and far more capable than the factor system. One of the things I learned very quickly with the programmable system I installed in my '74 was how much more aggressive I could get with the ignition advance curve. I ended up disabling the mechanical advance and doing all of the advance through the ECU. Basically, the car idled at 12-14 degrees and as soon as it came off idle it went to 36 degrees and stayed there. The engine was so much more responsive. The OE advance curve is primarily setup for low emissions at the expense of performance.
 
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