I've been tinkering with a few different options on my new build and wanted to share some info with folks on a cheap aftermarket solution using Megasquirt technology.

I've always been both somewhat impressed by Megasquirt, mainly in it's functionality and nice graphical tuning software "Tunerstudio", but also put off by the complexity of building a Megasquirt and strange wiring harness connectors.

I've put together a project, based on a small number of relatively cheap components that allows you to make a fully functional standalone EMS based on Megasquirt that will directly plug into your factory ECM harness.

Now, I made a decision to pin the megasquirt as a direct replacement for the '165 ECM on a TPI car, since that is the most popular harness in junkyards and in the aftermarket (for guys with carb cars wanting EFI), however it uses the same connectors as you TBI guys so you could easily repin your harnesses OR do your EMS to your harness specifications.

In ALL scenarios, this is designed around using a MAP sensor, however there is enough wires available for a hybrid MAF/MAP system if that is your goal.

Some disclaimers:

1) This is NOT for emissions controlled vehicles
2) If you're not interested in soldering, loading firmware, this isn't for you
3) This is NOT for everyone.

Now with that said, here is a link to my site with the info:

http://members.cisdi.com/~anesthes/p...om/megasquirt/

Total project cost is around $300, assuming you have a junk '165, '746, '747 or whatever ECM case to donate to the project.

-- Joe

 

very nice job!

 

Very cool. I sure wish I had a factory harness to work with but in the end I am happy with what I have. It sure would be cool to be able to use a factory computer case and make it look 100% stock.

 

Joe,
Were you referring to any of these articles?

https://www.thirdgen.org/forums/dfi-...asquirtii.html

http://www.diyautotune.com/tech_arti...pter_board.htm

http://www.diyautotune.com/tech_arti...lock_v8_v6.htm

 

No. That is a possibility, however it becomes expensive when you get the MS-II, relay board, adapter board, etc.

For guys that want to assemble their own MS-II, the MS-II is $278 and the relay board is $73. The adapter board is $28 but you need a D56 header.
So you can do this as cheap as $380 but you need to ASSEMBLE the MS-II which is a whole lot of soldering.

If you did it with an assembled MS-II, it would be $432 for the MS-II, $94 for the relay board, and $28 for the adapter with minimal (header) soldering. $554 if my math is right.

The way I did it, it's a $300 investment with very minimal soldering.

There is a bunch of ways to do this. I wanted to prove a cheap entry point without major component soldering, which is what turns a lot of people off.

I've got to take some pictures of my finished unit but basically, all I had to do was solder jumper wires between the MS module and the D56 connector from Racetronix. I did make a stepper IAC circuit on a second board, and I have an internal relay for the fuel pump. I'll try to snap some pix tonight. Very minimal electronics skill required to do it this way.

-- Joe

 

so - now that you've done it, how do you like it? I'm heavily modifying the engine on my 87 IROC TPI which is the 165 setup. Ive been looking at buying a megasquirt II and the adaptor, i don't really want to re-wire my car. But before I do that, i'd like to see SOMEONE running the system for a while, and how well it holds up.

 

I've been using MegaSquirt for a while. I have used version I, II, and now III extra. If you see yourself really getting into tuning and wanting lots to play with, I would push you towards the III extra that I run. MegaSquirt II will work great with a TPI engine. The hardware and processors used are very fast, much faster than the GM or FAST or accel stuff. It's just as reliable as the next ECM.

 

cool, thank you.

 

My car do run on MSII + adaptor board no problem, i do have it form very begining of adaptor being sold

best regards