Hello all - I'm going to be building a gbs zero with an mx5 donor ('96 1.8 if it makes a difference) . Still very much in the planning stage at this time.
I thought it would make sense to use a megasquirt standalone system from the start for the following reasons.
1. It would be a good excuse to make a wiring loom from scratch keeping it tidy and simple.
2. Lets me ditch the immobiliser and any other unnecessary items.
3. Makes it easy to cater for future engine mods.
4. I like the idea of building it myself and learning a whole lot in the process...a bit like the car itself...

Main reservation I have is whether I'm biting off more then I can chew...I'm not bad with basic electronics but the MS website boggled my mind a little. So I'm seeking a little assurance that you don't have to be a braniac to build and use one.

Also is it possible to wire it in parallel to the original ecu to begin with in using imputs only to log all the data and then use that same data to make your initial map?

Would playing with megasquirt help tweek things for the emmisions test or just or is it going to be an easy pass anyway on a bog standard mx5 lump? (on that subject do you have to run a cat on a '96 engine?)

Would you use all the factory sensors and can you buy the plugs to fit them without destroying the old loom (...in case it takes a while to get ms up and running and you want to use factory ecu)

And what would be the better choice in terms of MS1, MS2 or MS3

Thanks,
Luke

I built my own megasquirt it came from DIY auto tune it was straightforward to build, came with all components clearly labled and very clear instructions.

Work methodically following the instructions and test at the end of each assemble stage and you will be OK.

The software can be programmed to work with whatever sensors you use.

MS2 v3 would do more than you will ever need.

Don't know about paralleling not sure why you would bother tuner studio comes with basic maps which will run your engine.

MS isn't too bad to do and very educational. The website documentation is a mess which makes it look very confusing.

Their are better resources, such as:
http://www.extraefi.co.uk/support.htm
or maybe
http://www.diyautotune.com/tech_articles/tech_articles.htm

Regarding your ideal of parallel installation to reverse engineer the Mazda table. Interesting, but unless you can somehow detect the injector opening times and ignition advance then you might struggle to extract the required information.
Further I have only seen people struggle with parallel installations and ECU's don't like to share resistive sensors (i.e. TPS, MAT, CLT)

MS2 will do everything that you want, don't go microsquirt as you lose flexibility if you want to change something. MS3 is more capable still, but more than you need both in cost and complexity. MS1 is fine if you are just controlling fuelling, but controlling sparks gives you loads more control (i.e. advance, rev limits, boost rev cut, shift lights, etc. etc.).

matt

I built MS for exactly the same reasons as you and like you rather than buy a loom(s) I built bboth ECU and car looms. I found the build very rewarding and as pointed out educational.

All parts for standard engine components, injectors/sensors/idle vales all very accessible. Can't remember the exactly but I'm thinking you'll probably have to have a cat on the MX5 engine.

MS3 wasn't available when I bought mine, went with MS2 BG at first and then changed to MS2 extra to achieve larger tables for mapping.

Have fun.