Sure, I don't mind commenting on MegaSquirt. The other efforts, I don't have any experience with, but it appears none have gotten to the point where they're documented for a typical end user.
Derick Freese wrote:
The source code may be available, but it's only able to be installed on MS hardware that's made under contract by other vendors, such as DIYAutoTune.
More or less - you need an official B&G CPU and main board for the regular MegaSquirt line, or something made under license like the MS3-Pro. It has been this way from the get-go, although policies have become more written and official as the project grew and more people needed official guidelines. There has also been a bit more work at actively cracking down on unauthorized copies.
The MicroSquirt Module is one example of something that is a CPU, main board, and licensing in one package, and they can be ordered in bulk to get the costs down.
There are a couple reasons for the policy. It's not just to ensure Bowling & Grippo get paid - although they are now currently working on MegaSquirt and related projects full time. The other two reasons for this are quality control (we had a couple unauthorized MegaSquirt clones with severe issues, such as Fuel Injection Pro's boards that consistently burned the traces on the injector outputs because they were too thin and couldn't carry the current required) and support (yes, we've seen people ask for support on how to add mods to homemade boards when nobody has any idea how the thing is set up). Having a standardized product lets people who do support (like myself) get familiar with the hardware's quirks and behavior that would be very difficult if there were several dozen variations.
bentwrench wrote:
Also the MicroSquirt module was built with P&P in mind, plug that into an adapter board to support any extra hardware and make the appropriate connections to an OEM connector.
That is exactly where I'd head for this. If you want to make your own run of cheap plug and play systems for a niche application, get a MicroSquirt Module, etch a couple adapter boards yourself or get them made from a short run PCB supplier (they're a lot of them out there, and the cost is cheaper than you might think), and solder on some connectors salvaged from junkyard ECUs. The DIYAutoTune.com MSPNPs add a third board with more supporting circuits, but this is not strictly necessary; it's more something we did to give it features above and beyond what a bare-bones plug and play system would cost and differentiate us from a couple other outfits that had adapted the MicroSquirt Module to plug and play systems.
Watch out for the plug & play customers = most are support nightmares
I wouldn't necessarily say they are support nightmares as much as that they have higher expectations (as they very well ought to!). They'll expect good install documentation, a map that can run a stock example right out of the box (and possibly maps for their modified engines too), and support to be ready if they need it.
Between the work to design an MSPNP and the testing, dyno tuning, and documentation it takes to get to the point we can meet the support expectations of plug and play customers - THAT is why we have a 10 unit minimum. If we set it lower, we would have to charge considerably more to cover the R&D expenses of putting something together in order to make any money on it, and I can't imagine people willing to pay something with a four figure price tag for a niche market ECU unless it's for a very rare and expensive car.