My current megasquirt experience

[hoshy]

Just wanted to update anybody who's interested in the current status/costs/experience etc that I've had with Megasquirt.

A couple of years ago I wanted to put the Eaton m45 mini cooper S supercharger on my m40... Never really got around to it but now the project is happening though the car has changed to my current iS.

Obviously I needed standalone system for the supercharger but it was something I wanted to do anyway - supercharger or not - just for the experience and "fun"

I reckon there's three routes to take with megasquirt:

1. Buy a ready made kit and have somebody like Ant fit and map it.

2. Buy a ready made kit and fit/map yourself.

3. Buy an un-built kit and build, fit and map yourself.

I'm a tinkerer by nature so the ONLY route for me was the self-build kit. I've got a bit of an electronics background but don't really know much about cars, but want to learn so MS helps with that side a lot! If you want to really learn about engines, ignition timings, fuel injection systems and all that goodness then a self-built/installed and mapped MS is definitely the way forward.

For me the costs were as follows:

MS Kit: 170
Wide-band: 170
Air temp sensor: 20
Stim(recommended to help build the kit, can be sold): 40
Centre exhaust with bung for wide-band o2: 20 (cheers Dan!)
Wire for hooking in: 10
USB to serial adapter for laptop: 15
Old broken ECU for the loom connector: free, complements of a blown ignition driver
Piping for MAP sensor: free, thanks to daddy (probably a fiver to buy)

Stuff I already had: Multimeter/scope, soldering kit, laptop

So roughly 400/450quid - for a complete home-build set-up that you can map on the road.

Doing the initial build is pretty straight forward. Working out the wiring/resistors, extra connectors etc for the ignition side was the hardest thing probably and even that wasn't really an issue. You also need to add a couple of very small additions to the board to get things like idle control and tach signal out of it (stuff that I haven't done yet -- but it's easy enough I'm just lazy )

After that the thing actually started the car pretty much first first turn of the key. I then had an issue because I had the crank sensor wired in backwards which wasted me a few hours. Now I have a problem with not being able to rev above 5500rpm which is bloody strange but I've been getting help from various folk in the MS community. Of course if you buy a ready made kit and loom you're less likely to have problems like this and you can of course get support from the supplier.

A good option to buy ready-made is from http://www.extraefi.co.uk/ where you'll be buying form Phil Ringwood who's one of the people who actually wrote the extensions to the basic megasquirt that turns it from just a fuel controller in to a full engine management system (known as MegaSquirt'n Spark-extra). Basically he's one of the UK's top MS gurus

If you want a self-build kit, you can try getting hold of Bill Shurvinton on the http://www.msextra.com/ forum --he supplied mine. I believe the forum also has links to various uk suppliers.

So - current status of my car is that it can runs on MS, and it runs very very well even with a rough map the power at least as good as with the stock motronic (up to 5500rpm) if not better, arse dyno of course.

Next steps for me are to fix up the air intake, idle control, tach signal and solve the 5500rpm problem then I can work on doing a proper map. I want to work it out on the road first using tools like MSTweak and MegaLogViewer, they can help you interpret the data logs that MS can record to help you map. Apparently you can get very good results on the road like this. Of course, this type of tuning requires time and a wide-band so for similar costs overall you could ditch the wide-band and send it in to be mapped properly and save the time. But for me half the point of it is to learn how to do the mapping.

Anyway. Hopefully that answers a few questions people might have about MS.

[Demlotcrew]

[hoshy]

Take another look mate. I wrote tbc first time because I wanted to get a link for the thread before I actually wrote it

[Speedtouch]

Useful info there. My latest E30 has MS fitted (courtesy of Flappysocks) so I need to do a little studying of this, so I can make proper use of it - certainly a fascinating subject. Also plan to fit an ICV soon.

Cheers,

[Kedge]

Nice one mate, so it's not too bad then starting from scratch with no knowledge of engine management?

My current thoughts are to get it running on the standard engine, then add ITBS abd get those running and then hopefuly by that time i'll have my engine build finished as well to go in.

I'll have to make an alteration to my current exhaust though since is a full stainless system for the wide-band sensor.

Can i ask why you chose to use MS rather than something like Emerald like Appletree uses?

Cheers
Dave

[e30_Turbo]

Nice write up dude!

MS is very "easy" once you get into it, there is so much to consider and I can totally relate to those whom find it all a little too much. I spent many hours scratching my head first time round as I bought a fully made unit with loom and sensors etc, doing it this way I didn't learn anything about how it works internally.

Having built my current V3 from a kit I picked up on how it works and that was the key to start to work out how it all works together. Adding the mods like wasted spark etc does compicate things to start with but once sorted is worth the effort.

The 'fun' starts when you start tuning, make small changes and see how it goes, you'll know when you're getting the hang of it, you can FEEL the difference

*** There is certainly a case for tuning on a RR with someone who knows, it would have saved me a few £Â£Ã‚£'s if I had done this back in the day ***

hth, Mark.

[Turbo-Brown]

Is there a "light" version of MS which just has a fuel map in it?

It'd be handy if there was as that'd give lots and lots of mappable control over solenoid valves....which would be handy!

Think I'll e-mail Ant!

[hoshy]

Cheers Mark - I can't wait to get to grips with the actual tuning side. It's gonna be as.

Alex - Megasquirt is actually just a fuel controller originally but you can easily make use of the CPU outputs to control various things at your discretion. Other options are http://www.microsquirt.info/ probably many other options too.

Dave - Emerald vs. MegaSquirt. For me personally I like the idea of MS. It's community driven, cost effective and a great learning experience.

There is a very good case for a commercial product like Emerald. You've got warranties, and formal tech support. If it all goes wrong there's a company to moan at. With MegaSquirt these things are optional. If you pay the likes of Ant to fit and tune MS - you can moan at him to fix it and it's his responsibility to do so. If you buy a ready-made kit from a company, you can expect technical support from that company. If you don't want that kind of thing and fancy the challenge of the DIY approach - you can have it, but like the zone you'll have to be patient with people who can offer you advice because they're doing it to help you and they don't owe you anything.

I think I said on another thread., If you just want to pay your money to a professional and make your car faster then it's not really your decision which management system to go for - just accept that particular tuner's recommendations and trust that they know what's best. So it really depends on how you want to go about things. Sounds like you are in to the DIY approach so you should choose how deep you want to get involved with the management and mapping side. If you're doing an engine rebuild why not make the extra effort and know how your engine runs inside out 100%

[FlappySocks]

There is so much info out there for Megasquirting your E30, then why use anything else? Take a look at what they are doing over at the E30Tech forums. There are so many options available now, from building at component level, to DIY plug & play builds. There are even PCB's available now, specifically for the Motronic system. I am developing a multipurpose PCB too, to fit inside the Motronic case, or just as a bolt on extra

[hoshy]

Ohh nice! A 2nd vr input stage would be a nice addition for the m42 boys I presume it would work the same with the vb921s? Just out of interest, what are the trade-offs on the 921s versus 540s? I noticed that the 921s are rated up to 6amps and my stock bosch system was running 7amps but 6 is enough from what I understand.

Just a little update for anybody who's following. After getting the wideband in I lashed up the set-up in to the car and drove her 200 miles mixed motorway/back roads. There's a feature of the Megalog Viewer program that can look at your wideband output in the datalogs that MS can write out and make corrections to the fuelling table automatically.

I stopped maybe 10 or more times to go through the cycle of logging, import and update the fuel table then log again and got the fuelling a lot better - one strange thing that I've got a question on below but I could see that the graphs that the Megalog viewer were displaying were less and less erratic. I also refined the spark table and she seems ok.

Not spent any time on the rolling road yet but as soon as this 5500rpm problem is sorted I will.

The one thing I noticed in Megalog viewer was that the VE table analysis seems to be targeting 15.8:1 AFR. I set lc-1 in the megatune configurator, in megalog viewer and set the switch point to 2.5v. Anybody have any ideas?

[e30_Turbo]

0-5v is spread over 11-22afrs IIRC, so 2.332v is 14.7 AFR, not 2.5v

All depends on how you've setup the LC-1 and MS, I left the default settings in and it worked fine.

Just need to ensure all the settings match up, HTH, Mark.

[hoshy]

Cheers mark. perhaps I got wrong info in the default setting for what stoich was. Read it was 2.5 - I'll hook the laptop in and double check mine. I used defaults also so you're probably right.

On the plus side. Today I nailed down the 5500rpm issue to the VR sensor and have improved matters so it revs comfortably to about 6600 now. That'll do until I can go see bill shurvinton to get it done 100%.

[hoshy]

Turns out that my lc-1 is set to 2.45 for stoich but the problem I was having was that megalog viewer uses the afr target tables even if they're not set for use in megatune. I only noticed when I clicked to get the advanced options tab which for some reason I hadn't noticed before. Things are really starting to get going now. Driven about 400miles on MS this weekend and she's feeling gooooood gonna run her to work and back now and see how the eco is on day to day stuff. Still got some mapping to do too of course. Dyno next week and watch this space for before and after dyno runs vs. the motronic.

[FlappySocks]

Ohh nice! A 2nd vr input stage would be a nice addition for the m42 boys

Maybe for the second revision, depending on feedback.

I presume it would work the same with the vb921s? Just out of interest, what are the trade-offs on the 921s versus 540s? I noticed that the 921s are rated up to 6amps and my stock bosch system was running 7amps but 6 is enough from what I understand.

921 are rated closer to 7 amps, and they have a current limiter which cuts in somewhere above 7.5 amps. The 540 should be better suited for PWM applications, such as this (3-wire ICV), were there is no pesky current limiter to get in the way. For a good alternative to 921's, then I use Fairchild ISL9V5036P3 IGBTs - cheaper too.

[hoshy]

Oh shit - sorry I've just looked again. I thought the three transistors were for ignition, but I can see there's two for idle pwn and one for boost control now. Hence my above question... duh And, yes - looking at the vb921 datasheet, I cna see it's 7.5a limit I got confused again. Actually the interesting difference between the stock motronic and the vb921 is that the 921 is rated for a lower VOLTAGE, rather than current. IIRC there was about 100v difference in the motronic to the MS w/ vb921s

[FlappySocks]

Some of the MS boards I have been putting together have required extras, such as boost, which are a pain to incorporate onto the 3.57 board, hence the small PCB. Ignition drivers only require a resistor, so no hardship to bolt directly onto the case.

Looking forward to getting the shift lights working. I was thinking about replacing the SI LED's for some higher intensity LEDs for the shift lights. Maybe have them double up as a warm up indicator or something.

[e30_Turbo]

Is there a "good" value LED to use on low voltage systems?

I ask as I fitted an odd one to my LC-1 and it caused all kinds of funny issues, eventually it packed up and I used a much older and dimmer LED which works fine. Just wonderd if there was a rule to these things.

@ Hoshy, I'm gonna try and fit the IAT into the TB tonight, having lost the IAT port by changing over charge pipes, looking forward to some drilling, tapping and swearing tonight!

[FlappySocks]

You usually need to use a resistor wired in series of the LED, otherwise you will burn it out/reduce it's lifespan.
Use a LED Resistor calculator like this one
http://ourworld.compuserve.com/homepage ... en/led.htm

[Speedtouch]

Is there a "good" value LED to use on low voltage systems?

I ask as I fitted an odd one to my LC-1 and it caused all kinds of funny issues, eventually it packed up and I used a much older and dimmer LED which works fine. Just wonderd if there was a rule to these things.

Use a suitable current limiting resistor in series with the LED; you work out the voltage and current that the LED needs (will be in the spec when supplied, but usually around 2.2V and 20mA), subtract the LED voltage from the feed voltage to give the voltage drop across the resistor, then it's a simple use of Ohms Law to find the resistor value: R=V(dropped across resistor)/I (LED current).

So, for instance to run an LED from a 5V feed you would want R=(5-2.2)/20*10^-3 = 140 Ohms.

[hoshy]

Some of the MS boards I have been putting together have required extras, such as boost, which are a pain to incorporate onto the 3.57 board, hence the small PCB. Ignition drivers only require a resistor, so no hardship to bolt directly onto the case.

Looking forward to getting the shift lights working. I was thinking about replacing the SI LED's for some higher intensity LEDs for the shift lights. Maybe have them double up as a warm up indicator or something.

Oh, reusing the SI lights is a nice idea. I think there's lots of scope for SI/eco gauge mods with MS. Not seriously looked in to any yet. got to do the tach output first!

[hoshy]

Is there a "good" value LED to use on low voltage systems?

I ask as I fitted an odd one to my LC-1 and it caused all kinds of funny issues, eventually it packed up and I used a much older and dimmer LED which works fine. Just wonderd if there was a rule to these things.

Did your lc-1 come with an LED in the box? Mine did but I don't recal seeing a series resistor so I assumed that it was internal to the controller. LED is clearly not "overdriven" in any case. I wonder if later LC-1s had a mod for this?

[FlappySocks]

I think there's lots of scope for SI/eco gauge mods with MS. Not seriously looked in to any yet. got to do the tach output first!

There sure is a lot of scope... I have so many ideas for MS mods. Just no time to implement them

In my day job, I develop satellite tracking kit, GPRS, and CAMBus stuff. I'm itching to get this all hooked up to MS in some way.

The tachometer output is easy. A 10K in-line resistor worked good for me.

[hoshy]

I think there's lots of scope for SI/eco gauge mods with MS. Not seriously looked in to any yet. got to do the tach output first!

There sure is a lot of scope... I have so many ideas for MS mods. Just no time to implement them

In my day job, I develop satellite tracking kit, GPRS, and CAMBus stuff. I'm itching to get this all hooked up to MS in some way.

The tachometer output is easy. A 10K in-line resistor worked good for me.

I hear you. I spend too many hours of my working day looking at MS / e30 stuff - this post being case in point

Somebody mentioned using the injector pulse widths on the eco gauge which is a nice plan.

I like your idea of using SI lights as warm-up. You could even implement a variable rev-limit like the e46 m3. I'd like to have some kind of warning light from MS too - if certain sensors fall out of scope just ground an output; more of an MS software mod really though.

what other ideas do you have?

[FlappySocks]

what other ideas do you have?

How about a backlit touch screen LCD that fits in the dashboard where the OBC/clock goes? I have the all the kit including an SDK to make it. Just haven't the time. Too many people bugging me for MS kit

The satellite stuff I develop has an external serial port on it and would be quite easy to interface with MS, which could expose it to the internet. With some sort of Web based Megasquirt backend, the possibilities are endless.

[hoshy]

what other ideas do you have?

How about a backlit touch screen LCD that fits in the dashboard where the OBC/clock goes? I have the all the kit including an SDK to make it. Just haven't the time. Too many people bugging me for MS kit

The satellite stuff I develop has an external serial port on it and would be quite easy to interface with MS, which could expose it to the internet. With some sort of Web based Megasquirt backend, the possibilities are endless.

Ahh ok- You're talking the "extended" features I thought we were still on the SI stuff.

A mate of mine was running an MX-6, also on MS, with a 7inch touch screen lcd moulded in to the dash and a full xp pc in the back. A bit of overkill but he had Megatune, sat nav and mp3 playback etc. Was a very nice set-up. Would prefer a non-ms solution if possible though. Perhaps something embedded.

I like you idea about the screen to fit were the oem click/obc is. I was thinking of moving the heater controls down near the ash tray, then move the radio a bit lower to free up space for a decent sized screen. Have you got any links on the screens. What interface do they use?

[FlappySocks]

Have you got any links on the screens. What interface do they use?

Cant recall the name of the manufacture off the top of me head, but it's got an inbuilt CPU. Something like a PIC but with a bit more grunt. I figured it would be handy for basic configuration changes, but used mainly as a display. It has a few analogue inputs too, so they could be hooked up to say oil pressure.

The other thing, regarding displays I was thinking about, was using a Nokia 770/N800 web pad/terminal. (just cos I already have one, and its popular with the CANBus guys), and link that to MS. A bit less of an overkill that installing a PC in the car.

[hoshy]

Have you got any links on the screens. What interface do they use?

I was thinking about, was using a Nokia 770/N800 web pad/terminal. (just cos I already have one, and its popular with the CANBus guys), and link that to MS. A bit less of an overkill that installing a PC in the car.

also a good plan. I suppose with a blue tooth serial dongle I could get my n95 hooked up too

[tim_s]

what was the VR issue in the end then mate?
flappysocks - i pointed a friend of mine to your ebay linky to have a 3.57 built a wk or two back. Was wiring it in yesterday for him, should be there soon

[FlappySocks]

also a good plan. I suppose with a blue tooth serial dongle I could get my n95 hooked up too

Great minds think alike! I got myself a "AIRcable Serial3" dongle, which looks like just the job. I got my Nokia talking to it, from a command line interface.

[FlappySocks]

flappysocks - i pointed a friend of mine to your ebay linky to have a 3.57 built a wk or two back. Was wiring it in yesterday for him, should be there soon

Great stuff. Good luck with that. If you get any VR problems on the 3.57 board, a few people over at E30Tech has said that adding a 10K to 12K inline resistor fixes it.

[tim_s]

cool. are there known issues with 3.57 boards then? Is yours a 3.57 then hoshy? I've done a few v3 installs and never had any trouble.

[FlappySocks]

The VR is a known issue, at least according to some of guys over at E30Tech. More common on V3.57 board apparently at high RPMs. I updated my wiki the other day accordingly.

[hoshy]

Mine is a v3 Tim. It seems it's a weak vr signal that was the cause. Moving the sensor even a fraction of a mil closer (I aggressively sanded the vr bracket ) helped get me up to 6500, still issues above that though so not 100% sorted. Unfortunately the m42 vr bracket isn't adjustable.

Flappy (sorry your name escapes me atm) If you wanna send me what you've got so far I'd be happy to have a play and give some feedback.

[FlappySocks]

Flappy (sorry your name escapes me atm) If you wanna send me what you've got so far I'd be happy to have a play and give some feedback.

lol, it's Stuart. Play with which bit?

@Tim, If you have VR issues, let me know. I might ship these board with resistors in the future if it's an issue. (pm me if you need any).

[hoshy]

Flappy (sorry your name escapes me atm) If you wanna send me what you've got so far I'd be happy to have a play and give some feedback.

lol, it's Stuart. Play with which bit?

ahh yes. I even knew that.

You said you had some command line tool. You've already hooked in with a nokia via bluetooth?