Slashdot Mirror
Build Your Own Fuel Injection Computer
renaissance-redneck writes "I was searching for details on assembling a fuelie setup from junkyard parts when I stumbled across this: 'MegaSquirt is an Experimental Electronic Fuel Injector Controller for Internal Combustion engines. Its main goal was to create a simple fuel-only controller that could be easily reproduced with cost-effective components.' If you've got the time and the skills, it beats spending $2000."
But I'd rather be blown!
This raises an interesting question - namely, when are we going to see more hacking done on modern engine control computers?
I don't mean the current crop of "chips" that increase horsepower by overriding emissions control code, or remove the rev limiter code, I mean real, creative hacks.
For example, a friend of mine and I were discussion this possible hack:
On an engine with sequential multipoint injection (one injector per cylender, near the intake valve), could one modify the ECU so that, when the engine is under minimal load, instead of firing the injector on every intake stroke, it would fire on every other intake stroke - in effect changing a four stroke engine into an eight stroke engine?
In theory, this would allow you to run a leaner mix (leaner = hotter burning) without burning up the cylinder, and you could save fuel. When the ECU detected the engine being placed under more load, it would start firing on every intake stroke (and remap to a richer mix).
Of course, I suppose the reason we don't see this is because hotter combustion = more carbon monoxide produced instead of carbon dioxide.
Now, if I could just get anoncvs access to Ford...
www.eFax.com are spammers
Does this mean I'll have to gas up my computer now? The oil companies are controlling everything nowadays...
Would my auto insurance cover any injuries sustained while doing this?
...does it run Linux?
However I would much prefer my car to continue operating afterwards.
Seriously though how long till you see *Hacked with Megasquirt* stickers on all the rice mobiles going around?
37 - what does it stand for really...
Not this weekend! I build my MS back in December but didn't get my new motor together until about a month ago. Now I'm about ready to start putting it all together and /. finally notices the project.
;)
h tm
/ phpBB2/modu les.php?set_albumName=album43&op=modload&name=gall ery&file=index&include=view_album.php
So of course just when I need the site the most it will probably be overrun and unavailable
Seriously though it's a great hardware hacking project. Quite a few revisions to the basic system have been made by the users and there are even a few spin-off projects (MegaSpark, MegaSquirtAVR, MegaJolt, MegaView, MegaTune, MSTWeak3k....) all of which were created by users of the system.
It's based on a stripped down simple version of the DIY EFI-32 project that aimed at building a homebrew version of the GM computer but was getting so complex it was turning some people away.
If the main site does get slashdotted there's the Yahoo Group: http://autos.groups.yahoo.com/group/megasquirt
The MS FAQ:
http://members.shaw.ca/megasquirt/MS%20FAQ.
And a few photos of my own project for those of you you just want to see the pretty pictures:
http://www.americansandassociation.org
--- Juggle juggle@hitesman.com
confidently expect to see a lot of geek car enthuasiasts being nominated for Darwin awards after this mod.
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
That aside, that's pretty cool. I wouldn't be willing to put one in my car, but it's still cool. Plus you could hack up the monitor circuit so you could connect it to your incar Linux PC with a little LCD panel to watch your engine in real time, or maybe use you're engine's performance (rpms, mix, etc) to somehow controll the music being played. The pointless add-on possibilities are endless.
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
I'd rather see a Mass Air Flow version of this. Maybe because I'm a little biased towards Ford's system, but MAF seems to be easier to modify. Supercharger? Turbo? No problem! Just make sure you plumb the MAF sensor before the blower or turbo inlet.Of course this is on a stock system, stock or mild cam, and good exhaust. No other modifications necessary.
OTOH, with access to the assembler code for the EFI controller, you can run any setup you want, but you'll have to spend a couple days driving around with a laptop in the passenger seat adjusting A/F ratios and various timings until the engine runs smooth. This is also a great option for the multitude of oddball engines that never had an EFI option, or if you're like me and don't like those overpriced Rube Goldberg TBI setups Holley makes.
Sounds like one of those pills advertised in the back of mens magazines or through spam...
They do sell other standalone setups which we use for Rallying (Yes, like you see on SpeedVision, or what you have played on GranTurismo or other Rally racing game) - examples: Link ECU, MoTec, AEM-EMS
All of the above allow control and modification of all elements of the car via a serial link to a laptop. You can even data log and so forth.
Depending on where you buy it and so on, it's not going to be as cheap as the product listed here - but, you gain boat loads more functionality. For Rally racing like we do - we need the control/fine tuning ability to change fuel maps, ignition timing, Anti-lag for the turbo (amongst other things) to squeeze out every bit of performance that we can to go against much better funded teams.
-victor
Some people are replacing stock computers in more modern cars for performance reasons, and some are putting them in older cars, and getting some impressive results. And, yes, you can hook up a laptop for on-the-fly tweaking. Now I want a car.
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
It's a pretty cool way to get supercar performance from lesser (read: cheaper!) vehicles. My daily-driver Miata has the factory 1.8L engine, force-fed 15psi boost by turbo. It puts out 250hp/250lb reliably (up from factory 120hp or so) and, thanks also its low weight, it outperforms 'Vettes -- except for top speed, and excluding the awesome Z06, of course. But then I paid about $20k for my car, not $50k... (Check out Flyin Miata for more info, no affiliation except as a happy customer.)
I'm not using the MegaSquirt (using Flyin Miata's Link ECU instead) but the concept is the same. There is a HUGE need for an affordable programmable ECU among us automotive tinkers.
Is it *that* obvious that all computer geeks computers less valuable then their automobiles?
There is no sanctuary. There is no sanctuary. SHUT UP! There is no shut up. There is no shut up.
If all you get is the injector pulse, you can buy a system for much cheaper than $2000 US!
Blar.
The modern ECU's control more than just the air/fuel (by reading 02 sensors, etc.). They alter things like timing and monitor a host of things.
Many in the Honda crowd use an Apex'i S-AFC (or similar) to attach in line with the computer to adjust various things. Additionally you can buy other controllers and the like to adjust realtime at will.
This thing is impressive, but is no replacement, it's a piggyback, and has a long ways to go.
Colossians 2:8
Scary....I was just talking to a friend about attempting to make an OSS version of Ford's EEC (IV or V) with nothing but software and some jerry-rigged type of wiring harness. I definately think it is possible.
I haven't had time to get into trying it just yet, but after recent issues with my car (fixed now), I thought up the idea. If time permits and I actually do get something hacked up, I will surely post it as OSS for all the world to play.
Then again, if I or somebody did make something like this...what would Ford's reaction be? I mean with all the casual sueing going on recently.
Oh well!
Go to this link and see what people have done already. Lotsa hacking going on there...the entire GM Engine Computer has been reverse engineered. I drive a GMC Typhoon...and there are several guys on the "syty list" that have really taken apart the code, and made it possible to change all sorts of things. There is even a programmable box you can use to flip through various programs of timing and fuel.
Yahoo MegaSquirt Group This has the message archives, files, and links to MS related sites.
MegaSquirt FAQ This is the place that you should look for answers before sending to the list. If it hasn't been asked here, Lance is more than happy to add the Q/A to the FAQ. It's very well organized and will take a novice through the whole process.
Since Bruce and Al's site was already linked, I'll forego that link. The best place to start is the Yahoo group, since it really is the nexus.
Just a couple of quick bits. If you are planning on using GM TBI injectors, get some 2 ohm 25 watt ballast resistors FIRST.
Second, if you are planning on using a distributor for the tach signal, you are best off by using the hall sensor directly. A lot of VAG vehicles have reported noise problems on the tach signal.
These are really the only 2 things I'd want to caution about first.
All in all, the MegaSquirt is a good system for DIYers because it bypasses all of the complexity of factory systems. You can use it with most factory sensors and it performs great. One of the bread and butter applications is replacing CIS with EFI, many people have done it.
BTW, my engine is the 1991 CBR 600 F2 engine on the IT Runs! page.
Ok; It seems that engine tuning isn't the biggest geek topic. That suprises me, since a few years ago when I got my first car, I learned everything I possibly could about every nook and cranny in it, engine included. There's a lot of interesting things.
This project isn't of interest to most big engine tuners right now, but it could be. The Megasquirt - which only has fuel injection controllers, you still need to time your ignition spark, a much more difficult problem. Replacing your cars computer right off will not get you much - it will probably cost you HP, because cars have many, many R&D hours into them and are already running at close to maximum efficiency. You can trade a little emissions for power, but in a modern Honda engine, it isn't much.
The big power comes when you use something like this in combination with a supercharger or turbo charger, then use additional control software to monitor your engine. Think of it like overclocking - you trade safety margin for speed, or in an engine's case, power. Instead of upping the voltage; You shove more air into the engine, allowing you to burn more fuel - added by a device like this, or something that's missing - a true, open source ECU replacement. It is a very difficult problem.
I love to irk people with big V8s - they are silly in the age of forged engine internals, ECU control, and modern design. You haven't lived until you've seen the expression on a Z06 corvette owner's face when he gets is ass handed to him by a built and tuned 1.8L Acura Integra. My current project is an engine buildup for my 2.2L Prelude, and I have ~300HP as a reasonable target. It's amazing what a little thought and hacking can do. You can't run much more power than that on the street feasibly, so penis issues aside - if you can make 300HP+ from a 1.8L engine - why bother with more? Troll in the extreme - you can design 1500+ HP V8's, but they're not driveable. IMHO. YMMV. YHBT. etc.
Engine tuning is a great hobby - if you can assemble a PC, with proper tools and the manuals, you can probably assemble a car engine. It might even run!
OBD-III scares the hell out of me. I don't plan on owning an OBD-III vehile, though.
There is another sister project or sorts to this one, called MegaSpark. I'll let you find the links, because I don't want to slashdot the poor guys. Ignition timing is a very difficult problem because you need very, very precise control. This is difficult to do. I have played around with this, but the approach I favour is to piggyback a microcontroller onto the computers stock signals and modify them how you want. Complete standalone systems can be very, very difficult and expensive to dyno tune and test.
..don't panic
Am I the only one seeing the pr0n possibilities?
668: Neighbour of the Beast
How is this any different from turning valves on a bigger than design carborator? Give me a break. If you program your computer wrong, your engine won't work, but I doubt it will explode or burn up.
This project is cool. It looks like free software and so, we can imagine the much will come of it. A nice use of this will be to put fuel injection on engines that were never had it to begin with. I wonder what it and some new heads could do for my 1970 VW van.
Friends don't help friends install M$ junk.
This device would be good for converting a carbed vehicle to throttle body EFI. With only two injector drivers though, it's ultimate usefullness is pretty limited. They claim you can batch fire several injectors at once (non-sequential EFI), but that is hardly 21st century technology and has all the disadvatages of carbs and TBI like crappy emissions, fuel economy, and idle quality. If your mullet-mobile's Quadrajunk needs another rebuild, then this might work for you. If your tastes reach any higher, though, you'll need one of those "expensive" EFI computers.
.sig
No animals were harmed in the making of this
This sig washed every five years whether it needs it or not!
This is a hard real-time application, so the thing had better have spare cycles available! :-)
While it sounds fast, car engine things happen at ridiculously slow speeds by computer standards. A 4 cylinder engine running at 6000 RPM still has 5 milliseconds between firing strokes to compute and time the next spark. An eternity to a computer...
...laura, whose car (1986 VW Jetta) has mechanical fuel injection and electronic (analog) ignition
Yeah, yeah.. Who needs all this fancy engine computer stuff.. Ever since I painted my Civic bright yellow (everyone knows yellow is fast), cut off the exhaust pipe, and added a 3 foot high spoiler (have to keep the wheels on the ground), it goes like twice as fast. You can clearly hear that my car has TEH POWER when I rev the engine at red lights. I am so fast you cannot even read my decals.
I used to work for an AUDI dealer we sold a lot of parts by Fed-EX to an outfit in Alabama including so many Controllers that Audi contacted us to find out if there was a failure prob. Seem that these people were modifing the new controllers to pump that little 2.5L V-6 to about 450 Hp (street and very driviable) drove one later it was a sweet mod.
Diplomacy is the art of saying "Nice doggie" until you can find a rock. Will Rogers
side note on air-fuel mixture ratios. Many people have heard that you need a mixture reation of 14.7:1. 2 important notes about this fact, first, that ratio is by mass, not volume, and so per unit volume, an engine uses thousands of gallons of air per unit of fuel. Most underestimate the amount of air needed. Second, that 14.7:1 is the stoicheometric (sp?) correct, or chemically correct mixture ratio. As in, that ratio is what should occur under lab conditions. Under real world conditions, you get your best fuel economy in the ballpark of 16:1, and your best performance in the ballpark of 12:1, which is why the farther you push that accelerator, not only do you need more fuel for more air, but the RATIO should increase, since obviously pushing the pedal further down indicates a desire for acceleration.