What's wrong with Megasquirt?

I was thinking about this a bit more and part of the problem is the mega manual and then the separate Extra manual. It would be a huge undertaking but it really needs a overhaul. I found it difficult to read at times and would literally get lost, as in not remember where I was in the manual so getting back to some particular bit of information difficult.

Open source is both a problem and the greatest thing. The problem is documentation. Information is scattered around the interweb. It also has led to MS being one of the most powerful engine management systems out there.

I tend to think of it this way:

Think of all of the "car builders" that you know that have screwed up the tuning of their carb with a simple screwdriver. Or have slapped on some performance part and then complained about it not working, even though others have gotten it to work just fine. Compare those types of folks to the ones that you've heard complain about MS not working for them. Where do you think the problem is in that situation?

In the Turbo-Dodge world, I've seen so many people failing to maintain a baseline to work from and just toss parts on an old worn out motor and are surprised when the clogged radiator causes it to overheat and blow the headgasket or worse. Unwilling to change their fuel filter or have their injectors cleaned, but will still crank their Grainger valve up and then piss and moan over a melted piston.

If you are the type that can follow the scientific method to troubleshoot and tune the product, then you'll do just fine tuning nearly anything. If you can't deal with the blinking clock on your VCR, you'll probably not want to go down this road.

dean1484 wrote: I was thinking about this a bit more and part of the problem is the mega manual and then the separate Extra manual. It would be a huge undertaking but it really needs a overhaul. I found it difficult to read at times and would literally get lost, as in not remember where I was in the manual so getting back to some particular bit of information difficult. Open source is both a problem and the greatest thing. The problem is documentation. Information is scattered around the interweb. It also has led to MS being one of the most powerful engine management systems out there.

They are two separate solutions and code bases, which is why they are not joined together.

I found that I needed to print them both out and put them in binders to effectively read them.

To find a particular bit of info, use the Find option in your browser or search using the Site:megamanual.com or Site:msextra.com in Google.

dean1484 wrote: I was thinking about this a bit more and part of the problem is the mega manual

Agreed. Everything you need to know may be in there but it if you can't find it what good is it.

It reminds me of this

The Handbook for the recently deceased said: Geographical and temporal perimeters: Functional parameters vary from manifestation to manifestation.

This thing reads like stereo instructions!

I think the earlier poster who said there are so many excellent tuning solutions for popular platforms nowadays that use the OEM ECU that MS has sort of gone by the wayside.

I shake my head every time I see a turbo DSM running Megasquirt, when a used DSMLink setup is $400 and uses the OEM computer, sensors, everything.

Same for GM vehicles and EFI Live or HP Tuners.

You name it, there is a way to program the factory ECU. For oddball swaps or cars never offered with EFI, its a decent way to go.

dean1484 wrote: I was thinking about this a bit more and part of the problem is the mega manual and then the separate Extra manual. It would be a huge undertaking but it really needs a overhaul. I found it difficult to read at times and would literally get lost, as in not remember where I was in the manual so getting back to some particular bit of information difficult. Open source is both a problem and the greatest thing. The problem is documentation. Information is scattered around the interweb. It also has led to MS being one of the most powerful engine management systems out there.

My biggest problems with the commercial aftermarket EFIs is that they do not offer any kind of source code. Let alone a book that's the source in a pre-machine version (say C).

Is there such thing as a MS C-book or code? If there is, then you can do a better job in tuning, since you know really how it works; and you can also help work on improvements.

FoundSoul wrote: We also have plug-n-play models for Miatas, and more in the works.

Just curious, but I assume the 1984 Toyota Celica is probably next on the list, isn't it? They sure are popular! I bet you'd sell ones of them.

With that out of the way, this is a really informative thread.

93gsxturbo wrote: I shake my head every time I see a turbo DSM running Megasquirt, when a used DSMLink setup is $400 and uses the OEM computer, sensors, everything. Same for GM vehicles and EFI Live or HP Tuners. You name it, there is a way to program the factory ECU. For oddball swaps or cars never offered with EFI, its a decent way to go.

How many of these solutions offer launch control? Flat shift? Boost control? Water or Methanol injection? Wideband support? These are just off the top of my head, the list could go on for a while.

93gsxturbo wrote: I think the earlier poster who said there are so many excellent tuning solutions for popular platforms nowadays that use the OEM ECU that MS has sort of gone by the wayside. I shake my head every time I see a turbo DSM running Megasquirt, when a used DSMLink setup is $400 and uses the OEM computer, sensors, everything. Same for GM vehicles and EFI Live or HP Tuners. You name it, there is a way to program the factory ECU. For oddball swaps or cars never offered with EFI, its a decent way to go.

There are LOT's of cars that don't have (available to the public) cracked ECU's. If I could opensource tune a BMW ECU, I'd be all over it.

MOST of the cracked OEM ECUs aren't capable of half the things Megasquirt is.

Just my two cents' worth: I've MSed an AMC 4.2, with a TBI unit. Biggest problem? Everything was a new system. Fuel tank/pump/surge tank setup was a bite. But the fuel injection itself? worked like a charm. Lots of work, thinking through systems, reading and rereading the megamanual, but that was the thrill for me. Got bored with the car, am now sorting out an '81 KZ1100B, which was an early FI bike. Am going with the MSNS and driving the ignition. Easy? No, but that's the fun. Now, would i 'Squirt a car my wife drove every day? Heck, no. But, then, she won't use a computer running a Linux OS, either. Knowing other guys who run MS, I'd say it takes a high "geek" factor. Maybe something else could do it better, but with MS, I did it.

I'm currently running a cracked ECU. I will be moving to MS. The things I like better:

1. The ability to run directly off of a WB02.
2. Better resolution - Stock ECU has great resolution below 2500, and it gets progressively worse as the RPM's increase.
3. Antilag
4. The ability to run high impedence injectors (and clean up my engine bay of that damn resistor box)
5. I'm sure there are more that I'm forgetting. Point is, none of this can be done on my cracked OE ECU.

92CelicaHalfTrac wrote: MOST of the cracked OEM ECUs are capable of 5x the things Megasquirt is.

just sayn.

After reading this thread I have concluded the Factory EFI's are just fine. My computer knowlege is perfect for my tuning of a set of SU carbs. Cracking source codes? Yikkes! Seting the needle level. That's doable.

alfadriver wrote: My biggest problems with the commercial aftermarket EFIs is that they do not offer any kind of source code. Let alone a book that's the source in a pre-machine version (say C). Is there such thing as a MS C-book or code? If there is, then you can do a better job in tuning, since you know *really* how it works; and you can also help work on improvements.

Yes.

MS1 code is in Assembler, MS2 and MS3 are coded in C. All release MS1 and MS2 source codes are readily available. There's a bit of a discussion going on about exactly "who owns what" in the MS3 code and the source code to that will be posted once those details are ironed out.

A note to Greg - cracking the source code is something that's really only needed for a very hardcore user who wants to know exactly what a variable is doing, or wants to write their own functions.

In reply to GregW:

You should probably keep in mind that the alfa driver does that sort of work as part of his profession. Dabbling in source code is not, I think, remotely required to deal with Megasquirt. It'd be kind of like saying you need to know how to write source code to be happy with your desktop computer; a few people might do that, most do not.

DSMLink does all of the above (wideband, nitrous, antilag, flat shifting, idle speed control for big cams, aux inputs, switch to speed density, boost control, etc).

Modern OEM ECUs are superior to MS in almost every way, its just a matter of getting them to do what you want.

DILYSI Dave wrote: I'm currently running a cracked ECU. I will be moving to MS. The things I like better: 1. The ability to run directly off of a WB02. 2. Better resolution - Stock ECU has great resolution below 2500, and it gets progressively worse as the RPM's increase. 3. Antilag 4. The ability to run high impedence injectors (and clean up my engine bay of that damn resistor box) 5. I'm sure there are more that I'm forgetting. Point is, none of this can be done on my cracked OE ECU.

And considering that E85 is not always E85, MS has the ability to interpolate between maps using a flex fuel sensor. This is the ONLY thing I wish I had the MS over an AEM EMS for.

sobe_death wrote:

DILYSI Dave wrote: I'm currently running a cracked ECU. I will be moving to MS. The things I like better: 1. The ability to run directly off of a WB02. 2. Better resolution - Stock ECU has great resolution below 2500, and it gets progressively worse as the RPM's increase. 3. Antilag 4. The ability to run high impedence injectors (and clean up my engine bay of that damn resistor box) 5. I'm sure there are more that I'm forgetting. Point is, none of this can be done on my cracked OE ECU.

And considering that E85 is not always E85, MS has the ability to interpolate between maps using a flex fuel sensor. This is the ONLY thing I wish I had the MS over an AEM EMS for.

Maybe I'm just lucky, but I've not had any issue getting good E85. The EPA site states the switchover dates for various regions. I just make sure to buy enough at the end of the season to get me through the winter until next March when it's back to the full E85 instead of the winter E70.

Of course there's the other issue with E85, namely that you can't get it everywhere so you might need to mix it with regular fuel.

93gsxturbo wrote: Modern OEM ECUs are superior to MS in almost every way, its just a matter of getting them to do what you want.

Sounds great. If you have a modern OEM ECU for a '74 BMW 2002 running an E30 318i intake manifold, fuel rail, and FPR, and an E30 325is throttle body modified with a Nissan 300zx TPS, and a IAC from a Jeep, then I'll take it. Otherwise I'll continue with my Megasquirt project.

Hoping to get it all together in time for the Mitty and the Megameet.

T.J. wrote:

93gsxturbo wrote: Modern OEM ECUs are superior to MS in almost every way, its just a matter of getting them to do what you want.

Sounds great. If you have a modern OEM ECU for a '74 BMW 2002 running an E30 318i intake manifold, fuel rail, and FPR, and an E30 325is throttle body modified with a Nissan 300zx TPS, and a IAC from a Jeep, then I'll take it. Otherwise I'll continue with my Megasquirt project.

In all fairness, he did already say that's exactly the kind of thing MS was good for.

BoxheadTim wrote: Of course there's the other issue with E85, namely that you can't get it everywhere so you might need to mix it with regular fuel.

Ah. Yeah, I don't do that. Motor go boom.