I am looking into megasquirt stuff and was wondering who out there has done megasquirt on their teener and how well did it work
what are the advantages and disadvantages of it and how difficult was it to properly set up, test, and tune?
Thanks,
Charles

Member Dave Hunt (DNHunt)

http://www.geocities.com/dnhunt2002/Dave91...l?1054739433412

Boy, there is some VERY good advice on his "Musings" page:

http://www.geocities.com/dnhunt2002/Musings.html

I've been looking into doing it. Unless you buy everything soldered together it can be time consuming. One person I spoke with had at least 40 hours into the whole project. You could probably do it faster by doing a lot of research ahead of time, buying a pre-soldered ECU and then copying what people have done here.

Advantages:
programmable
not 30+ years old
will work with non stock engines, (especially cams), etc.

Disadvantages:
Time
Learning curve
Maybe not as reliable as a manufacturer built ECU (there is always the potential for a solder connection to break, etc)

If you have a stock engine I think it's far easier to just keep Djet maintained. If you have problems with components (injectors, aar, cold start valve, etc.) then you have to sort those out before going to Megasquirt anyway. The only thing a Megasquirt will replace is the MPS and trigger points.

I'm planning on doing this very soon

Just waiting for my ECU to come in, already have like ten laptops I could use for this project, plus a couple of pocket pc's i could use

I'd be willing to solder a unit together for someone if they needed.


Britt, yours is comming partially assembled as well


Charles, man you are only a senior and you won the tranny!? Lucky guy

I just saw that

I was like

Yep
Now I just need a bigger motor
(Anyone willing to donote, pm me)
plus, a person in this neck of the woods without a phd can't make that much money unless they are willing to deal drugs (and I just don't have the time for that, too much to do on the 914)

and 914s cost money (especially good transmission rebuilds)

as for the assembly, I can probably deal with that since I have done a fair bit of elecronics work (and have a dad who has a BS in Electrical Engineering and a phd in Physics)

Thanks for the offers and information though
(gotta get rid of that L-Jet)

L-Jet saved my life.

Those wiring harnesses make great straps for climbing

Well, one of the nice things about MegaSquirt is that you aren't stuck with any of the old components. You can toss the AAR for a stepper-motor-controlled IAC, which can be calibrated to open at a precisely defined rate vs. temperature. You can program the regular injectors to pre-squirt some fuel just before cranking, and vary the amount of fuel provided during cranking or at low temperatures, which (If I understand this correctly) does away with the cold start valve altogether. You have a little more flexibility when it comes to choosing injectors (anything that fits; they all flow enough, IIRC). And most importantly, you can throw away most of the engine wiring harness and run new lines right to the MS unit, or the relay board. Of course, you can replace the wires and keep the D-jet but most people I know are afraid to touch it if it ain't broke.

I'd say the choice of whether to go w/ MS, a commercial setup, or keep the stock system is pretty personal. But it sounds (from a later post) that 914nerd has some backup and some relevant experience that make MS look like a great option.

I installed Megasquirt earlier this year, it works pretty well. I had a couple hiccups and it isn't tuned perfectly but it runs great.

If Jeff Bowlsby ever decides to offer his pefi harness it will make the job a lot easier, in my opinion the wiring is one of the biggest tasks.

I've done MS fuel only, MS extra fuel only, MS I extra with EDIS and now run MS II with EDIS and soon to be MS II extra with EDIS. I love the system.

Dave

I was wanting to do MS II with fuel only for now, and then switch to fuel+spark later.

If you want a more reliable system, you might want to give the new microsquirt a look. In beta testing now, but shouldn't be long. It uses a real ampseal sealed connector (we use to use those exact ones at GE for wash down applications), is surface mount, and conformal coated. A *MUCH* better board to put in an automotive environment. Plus, I love the fact it uses a standard external GM MAP sensor. Its truely a step in the "more professional" direction.

SMD

I'd lose the microsquirt.

I really like the new microsquirt !!!!


I had the 1st 914 /4 running a Megasquirt way back when it 1st came out..
(a fellow with a /6 conversion might have beat me by a few weeks )

Anyways, the MS has come a long way, there are people running it on $15,000+ engines so they must have some faith in it

It will be a learning experiance, there is no phone number to call or real tech support..even with all the forums for it, if you don't ask your question the correct way or it's been asked too many times, you might be out of luck and not get a response or at least not one you want....

For your L-jet....

Keep:
stock throttle body
CHT
injectors
intake plenum
intake runners
distributor


New:
TPS (optional not to run one)
air intake sensor (stock one is built into the AFM and not easily removable)

A wide band oxygen sensor is highly recommended for tuning.

I'm installing the L-jet back onto my 1.8 and once I do, I plan on datalogging all the info I can grab off the motor...in theory, one could take this info, plug it into thier MS and if the motor is close enough to mine, it should fire right up and run pretty decent....

I'd still fine tune it....

If you buy one of the pre-built units your wasting your time and money. May as well get an SDS and have the tech support.

No matter how you do your PEFI the FAQ/tech part of the SDS site is required reading.
www.sdsefi.com

I'm now at the point where I need a dyno where I can put a load on the engine.....I used a roller set up and it wouldn't get into boost.

YOU NEED a 5 wire wide band 02 sensor....some say you don't...but you do.

Also, it's a learning experience.....one that I probably won't do again...but then again, I haven't prurchased an SDS or aftermarket built system so I have no experince on that.

One good thing.....I haven't burned up the engine....and I learned a lot in the experience. How things work.....

Just remember - if you've got a D-Jet car, and your motor is in good mechanical shape and in stock condition, you're not going to gain much (if anything) in going to Megasquirt from a properly-functioning D-Jet setup.

The bugaboo here is getting a "properly functioning" D-Jet. The costs to do so aren't so bad. The ECU's are very reliable and rarely croak, and if they do, you can get them from the ads here or from Ebay for cheap ($100 or so). Injectors have a 100K mile lifetime (minimum), and can be cleaned up and restored for $20 a pop. Bowlsby can fix your wiring harness for a couple hundred bucks or sell you a freaky-perfect one of his own design for $400. The trigger contact points go for 100K miles and are about $100 a pop. The rest of the temp sensors are fairly cheap or can be rebuilt (e.g. AAR).

The "Death Star" component is the MPS. New ones are $1100 and the 049 is NLA. However, I heard recently that the old rebuilder, Bret Instruments, is now owned by Fuel Injection Corporation, and that they're using new components for the diaphragm and aneroid cells that are much closer matches to the Bosch OEM parts, which should improve some of the drivability/response problems noted with the old rebuilds. Combine that with having either Bleyseng or Bowlsby doing a recalibration ($100 or so) and you can have a reliable and dependable MPS for about $350.

Depending on the condition of your D-Jet, you may spend as much as $1K getting it into good condition - or a lot less, if you are able to find good used components. A carb conversion or a Megasquirt conversion isn't much more or less when done correctly. Drawbacks with conversions is that they often lower the resale value of the car, and often require a lot of tuning to get them to work well. For those who want a challenge and like to work on your car, this may be a plus! Just be aware that fuel system conversions aren't likely to result in your 914 suddenly being a Vette-killer.

Mike, I thought I had the first one?....hmmmmm

The search function is your friend...

I believe that I had mine since sometime in 2002 or 3...time flies.

Now with MSII fuel only. works great, less filling...

oops, it was Posted: Thu Apr 29, 2004 2:09 pm. thought it was before that....

yea, mike, but I drove mine.....

ouch, that hurts...hahahah...I drove mine for a little over a month, then broke an exhuast stud...and then.......

You and Dave do get a lot of credit for putting on the most miles with a Megasquirt

I just looked up some old notes...

I was talking to Dave Hunt in August of '03...

If one was going to use MS for fuel only, is there any differences between the various versions? For example I'm not clear on the functional differences between:

Megasquirt I PCB board ver 2.2
Megasquirt I PCB board ver 3
Megasquirt II PCB board ver 3

Hey Anthony.

MS I V2.2 is the version that has been around for a couple years. It is the cheapest version.

MS I V3 uses the same processor but has a redesigned PCB with supposedly better trace routing and some extra features built in. I have heard of people having trouble with the onboard flyback circuits while browsing the forums.

MS II is a new processor that can be installed onto either board. It has higher res fueling maps, spark control native to the code (no need to install firmware hacks), ignition coil drivers on-chip, better support for sensor configs, more idle control options etc.

I am running a V2.2 board with an MSII processor upgrade. I am not using any flyback circuits, instead I am using ballast resistors which is the quick and dirty (but effective) way to do it. I heard of too many problems from people using the flyback circuits with low impedance injectors.

I am using the AAR for idle control and a normal dizzy for spark. I get my tach signal from an MSD box instead of the coil (highly recommended). I am using stock CHT and IAT sensors, and a TPS that I bought from someone that I fabbed an adapter plate for (super simple). I am using a Tech Edge WBO2 controller and a Bosch LSU sensor (if I remember correctly).

Hope this helps!

I'm using MS II on a version 3 board and using flyback circuits with no problem. My tach signal is from the EDIS module via a VR sensor. I to use the AAR valve for idle as this is a simple and effective warmup control. The TPS is from the junkyard and I can't remember which car. I also have a Tech Edge WBO2.

The resolution in the injector control is the main advantage for our cars with MS II over MS I. With the large injectors that are stock the finer resolution makes tuning easier.

Dave

Dave,
Did you have to make the extra circuit for your taqch signal? My tach is not registering the signal from my MJLJ, am I supposed to be taking it from the EDIS insead?

I meant the tach signal that MS uses in it's calculations.

Trying to get the factory tach to work was a challenge. There are two ways I've tried. The fiirst was with a couple of zener diodes. That was a no go. The other was using the clean tach output on the EDIS module. EDIS 4 has this but I don't know about the EDIS 6. Anyway I took my tach apart and jumpered across something. I'd have to look for the picture. Someone else tried it before me and it worked. I'm bright enough to be a good follower

Here's what didn't work for me. I tried a bunch of values for the zeners and no go.

The /6 tach triggers off the negative of the coil (the "points"). Is the /4 the same? If so, the tach is going to be unhappy w/ just a 0-5V signal. I have a MSD and have this same problem - wont trigger off the tach output of it. I used a MSD tach adapter (8510?). I dont know the polarity of the MS/EDIS tach output, but it might be able to trigger a MSD tach adapter the same way.

The MSD tach adapter doesn't work with EDIS. I actually soldered a jumper across something. The problem is I don't remember what it was. I have a picture somewhere I just haven't found it yet.

Dave

For tach - there's a resistor you can take out of the tach (or jumper it - i forget) which will make it accept the signal from the edis (you can use the pip signal which goes to the Megasquirt if you don't have the other wire).

I've been running megasquirt since some time in 2003. I started with the regular megasquirt 2.2 board and the straight MS software, and then moved up to the megasquirt-extra code on the subaru engine. Now I'm running MS-II on a v2.2 board with the subaru engine.

I have been running MS v. 2.2 since April with no problems. I bought the car with a rebuilt motor and bad D-Jet system. Ran like crap all the time. I really wanted to retain the fuel injection so I went with Megasquirt. I am currently running fuel only, but I did upgrade to a Vanagon dizzy w/ Hall effect sensor, a Turbo Saab Ignitor and Volvo coil. Kinda Frankenstein style. (I love DIY wrecking yards Tach runs on the negative side of the coil like stock, but the Megasquirt tach input runs off the clean ignitor tach output. I will probably upgrade to fuel and spark eventually, but what I have now is a good way to start. It was complicated enough just setting up fuel. Doable, though, if one is willing to be methodical and have patience.

Also, I wanted to take this opportunity to publically thank Mr. Dave Hunt for his "ground breaking" work with the MS unit on the 914, and most of all for posting his findings on the web. I never got around to doing that. I used his msq files to get started and ran them for quite a while. Thanks Dave!

James

mike, ive seen turbo and blown cars on roller dynos before....... isnt that how they test it (putting a load on it?)

here is what they did when i saw it on TV and at a friends ricer shop...

get the motor up to like 3k... then start using the dyno brake (LOAD) and then the motor should start coming up on boost... release the dyno brake and start sampling from there.....

Yes applying load is how you do it, but not all dynos are created equal.

Some are simple inertial dynos, which just measure power. The other type of dynos are eddy-current, and some are water brake, other have what looks like train brakes mounted on the rolls. With these you can apply a load against the drive wheels.

Im surprised about not being able to generate boost on an inertial dyno though. With our old Mustang inertial dyno we tuned many turbo cars and got them into boost.

Our new Dastek dyno able to apply load etc..

I installed megasquirt over the summer after my djet system that had been refurbished with all new parts 4 years ago started acting up again. I didn’t want to cut the end off of my R.E.S. $$$ wiring harness nor did I want to deal with the messy look and finding the parts to make my own harness. What I did was gut an extra ECU I had laying around and made sort of a break out box for the MS system. I did the same with the TPS, gutted an extra stock one I had and wired the new one to the stock connector. The system I have now is pretty much plug n' play to an existing djet system and you have to look pretty hard to tell its not stock d-jet. Using daves maps as soon as I turned the key it fired up and even without tuning it I could already tell it was running better.

Now I can take my system and get a 2.0 djet car running on megasquirt in 15 minutes. Everything plugs into a stock harness. Just swap the D-jet ecu with my breakout box/MS ECU, swap the stock TPS with my TPS, plug 2 wires in at the FI grounds(MS triggers off the ground side), T in a vacuum line, then just turn the key. Every other part of the D-jet system can be left in place.

Having a digital system where bad sensors can be diagnosed by looking at a laptop is sure nice, even better when it looks 99% stock.

Ill see if I can get around to taking some pics here one of these days.

-James

Hey James,
I would love to see pics of your setup, in particular how you did the breakout at the ECU box. That sounds really cool!

Are you using 2.0 injectors? Do you have any problems with the idle pulse widths being too small? I am planning on using 1.7L injectors for my 2056 and they are oversized. The 2.0 injector flow rates are huge.

For your injector wiring do you just run the negative connections to +12V and switch the other side? I thought about doing that but in the end decided to make my own harness from scratch since my old harness was pretty tired. I bring +12V from the relay board back to the MS, fuse it and go thru injector resistors, then back out to the engine. It is a bit of extra wiring but it lets me keep all the fuses, resistors, ECU, wideband controller etc in the same place.

What TPS are you using?