pizza_guy

My 84 L69 Camaro stopped working about 8 months ago. ECM failure was what I eventually came to. That may not have been the actual problem, but it was a good excuse to convert to fuel injection.

I went with a Megasquirt II V3.0 to handle the TBI unit I had aquired. About halfway through the project, I discovered the EBL. I still don't know everything about it, but it may or may not have been a better route to go. I'll never know. I spent about $2000 total for a novice wrencher to turn a carb car into F.I..

I still need to tune it quite a bit, but the LC-1 wideband appears to be working correctly. I put a Walboro 255 on the stock sending unit, and replaced all the clamped rubber with AN fittings. The stock harness was reused, with some pretty minor modifing, and the MS fits up in the dash.

I'll let you guys know how the tuning goes if your interested, or if you have an RPM X Map ignition map for an L69-T5 on 91 octane, that would be awesome too.

To learn about Megasquirt:Megasquirt II V3.0

Toehead

I have a pretty decent SBC ignition map.

pizza_guy

That advance map works great!!

Does anybody else around here run Megasquirts??



I got it up to 45 mph, but it keeps stuttering and stumbling about 2000 rpms. Can't get past it...yet.

My dwell is set to 4.5 at idle. Is that about right for the coil-in-cap setups. Any less and it's not very happy.

laiky

what do the megasquirts run? just ecm?

dharrison

iTrader: (3)

what induction setup you runing with that?

86birdHT

iTrader: (1)

I know its not a SBC but i was thinking about putting megasquirt into my 1983 VW Rabbit GTI, since im planning on putting a DOHC motor into it and then eventually a turbo.

It doesnt seem to be TOOO much of a hassle to convert the car over, with wiring and whatnot, i havent seen a screen of the software setup on a laptop or anything but its so much better than stock engine managements.

Toehead

I'm running a stock TPI. The nice thing about the megasquirt is that it will run boost no problem. There are guys running 1200 hp drag cars with megasquirt.
In the event that I want to go to forcd induction, I only need to change the injectors and retune.

pizza_guy

I would whole-heartedly suggest the Megasquirt for boosted applications.

You should check out the site for your non-thirdgen questions about it, though. I put the link at the very top of the thread. I'll edit it to make it more obvious.

Today, here and now, it probably is a little(and just a very little) behind factory-type ecu's. However, in the near future, recent developments will put it in a class all it's own.

If you learn how to edit the code for MS, you could make it do just about ANYTHING!

Toehead

I agree. At the moment it can do everything that the 1200 dollar units do, with th exception of transmission control. Guess what... Within a month the CAN bus exspanson board will be released that will provide transmission control and many many extra outputs.
Not bad for a 200$ computer!
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Plus, you build everything yourself. That gives you a level of satisfaction that no amount of money can buy.

91RamAir Formula

I'm also running a MSI V3.0 which I just got running again finally after a fiasco with an intake trade so now I'm running a stealth ram on my 383 with a pretty big cam. I never could get my stock TPI 8pin ignition to work correctly so today I switched over to a traditional mechanical dist and it runs great I just need to work a little more on the tune. Toe head what year TPI is you ignition? and could you share your settings because I never could get mine to run right with the stock ignition.

pizza_guy

I am also sorting out ignition issues with mine. Damn thing won't quite mis-firing. It's not satisfying if it were easy, though.

Toehead

just a stock 8 pin ignition module with external coil . It worked first try actually...

What settings do you specifically mean?
I followed the wiring diagram and settings from the megamanual page.


I do have one problem that i have been chalking up to a bad ICM. My cranking spark seems pretty weak. That problem is unrleated to the megasquirt since the megasquirt does not control ignition at all until there is a 5 volt signal to the override pin of the ICM

Let me know what settings you need!

91RamAir Formula

I'm looking for your dwell settings and what do you have for the settings on the Spark settings page? Also are you running MSI or II.

Toehead

MS-II version 3.0

I'll check the other setting when I get home. Thats where the car is.

I'm sure you can get it eventually. It may be noise in the line.

pizza_guy

Yeah!!! I got it. The camaro drove 14 miles for the first time in 9 months.

I thought I had dwell issues too. Turns out I had my ignition settings wrong. You DON'T need any more than 3.5ms...4.0 at MOST. Period. If it misfires constantly, try flipping your ignition output settings. You may have burned something up if the wrong output setting was used.

I'm using the 7-pin module and the VR input circuit. MSII/V3.0
I use "rising edge" for the ignition capture since I'm using the VR circuit. If using the Hall circuit(recommended) you would need the "rising edge" since the signal gets inverted before reaching the processer.
EDIT: I was wrong, the VR circuit inverts a square wave signal, so you should use "rising edge" here as well.

My output was the opposite of what the MS site suggested though. I set mine to "Going low" and BAM!, everything worked great...almost. I'm not using the "high current ignition driver", and I think you would need to invert this if you are. Might check the site on that, though.

Starting is "trigger rise", and I'm using the "standard coil charging"

The only issue left for me is my wandering timing. Whenever I take control using the MS, my timing will drift around a 10 degree window. Whenever I don't take control and leave it all to the module it is rock solid. Not sure where to start on this one.

Toehead

Just got back from a drive myself!

Runs very well, although I did get stranded at mobil because i had forgotten that I had messed up my cranking pulsewidths and i didnt have my laptop with me. D'OH.

The only thing i'm worried about is pinging that i can't hear. I've never had an engine ping on me. I've heard them, but only third person. I'm afraid of missing a pinging condition and hurting something!

pizza_guy

Ya got a knock sensor?? You can wire it to input to your MSII and it'll pull timing similar to OEM ECUs. You probably already knew that.

If you have an WBo2 sensor, you might get anomalous readings when knock occurs. You may also have MAP spikes. Neither a really great way to do it, especially since a JunkYard knock setup would be very affordable. A sensor, a module, and a little wiring.

Toehead

The engine does have a knock sensor, and I have it in my harness. I didnt build a knock-sense circuit on my megasquirt when I put it together because in january it was an "experimental" feature.

It is much better supported now, and it seems people are using them with success. Are you running a knock sensor?
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as for your wandering timing, the only thing I can think of is a noisy advance signal from the engine. Mine appears rock steady. I took a voltage reading at the coil while cranking, and the voltage drops to around 9 while cranking. This is what is causing the weak spark. I think improved motor grounding will cure the problem, as I am only grounding the motor through the starter ground strap. the sensors, megasquirt, and coil are all grounded independantly to the negative terminal.

pizza_guy

I went with the knock circut to begin with.

It doesn't seem to be hurting anything, but I haven't gotten running well enough to really test it on the road yet.

Toehead

Sounds cool. Early road tests on mine show it completely driveable, with no stumbling. I actually snagged the stock VE table with tunerpro, and transfered it to my megasquirt.
Perhaps I will build a knock circuit soon. This is simple and just requires some proto-area wiring, correct?

pizza_guy

Yep, pretty easy. Just make sure to get the zener the proper direction.

http://www.megamanual.com/ms2/knock.htm

Oh, and I was waiting for your ignition settings if you've got em. I'd like to compare them to mine.

Toehead

What i am going to do is create a knock count LED graph gauge. It will be adjustable. I ordered the parts off of digikey tonight, i'll let you fellas know how it works out.

pizza_guy

Wow, that sounds cool. I just put a PNP transistor on the signal from the ESC module. It lights an led on my dash when knock occurs. It's kinda hard to catch unless the knock is bad.

Are you following a schematic?? Maybe you could link to it perhaps?

Toehead

well, seeing as how you know how to use a PNP transistor, you should be all set!
I am actually doing the circuit mostly myself. i asked my ECE (i'm mechanical, but i need to take an ece lab) professor to suggest a good LED bar graph driver. He suggested a lm 3914. It creates a bar graph with 10 leds. It lights them based on the ratio of input voltage to vcc. If you use a PNP transistor to charge a small capacitor with an adjustable (potentiometer) path to ground, and use the voltage across the capacitor as the input, you can easily get it to graph. As the pnp detects a knock, it charges the capacitor. This capacitor will then discharge through the potentiometer, so the graph will peak and slowly go down. If the knock occur frequently, the capacitor charge will approach Vcc and the graph will illuminate all 10 leds. I will put a buzzer on the top LED. By adding potentiometers and tinkering with the capacitance, you can adjust how fast the capacitor charges , IE how many knock counts per LED, and also how fast it discharges. You can also put a switch to short the capacitor and reset the graph, as well as a 555 timer to clear the graph after a specified time with no knocks.


Have at it!

pizza_guy

Ahhh...didn't think of the 3914. I've got a few of them lying around. I'll add that to the list of things to do. Wow, I could use something like that for so many things. I wonder how you could test one of those on the bench. I COULD force the motor to knock to tune it, but I really don't want to.

I'm currently using a 3914 to convert my WBo2 signal from analog to a graph of led's mounted on a dash plate. Gotta love these things!