The beginnings of a Megasquirt how-to guide

[icingdeath88]

Originally Posted by BackWoodsBob

so op. will the plug and play board work with a stock unmodified harness or is using that board a must? still contemplating standalone vs aem fic8....

The DIY Break out board is the best way for an SVX, but since you've already been through the wiring once, you might be better off just splicing it into the harness. I'm not sure without seeing your setup.

[BackWoodsBob]

As I'll be rebuilding my spare engine here soon, I wont have a spare vehicle to 'test' my setup on so it has to be removable. So I'd rather be able to plug/unplug the ecu quickly once I'm done testing a tune. Which is kinda why I'm leaning towards a piggyback, cheaper and I can set the modification tables to 0

[icingdeath88]

Originally Posted by BackWoodsBob

As I'll be rebuilding my spare engine here soon, I wont have a spare vehicle to 'test' my setup on so it has to be removable. So I'd rather be able to plug/unplug the ecu quickly once I'm done testing a tune. Which is kinda why I'm leaning towards a piggyback, cheaper and I can set the modification tables to 0

Then if you go the ms route, I think you should build a breakout board. I'm going to start making a new breakout board for myself in like a week, so I'll post an excel of the pinout soon.

[BackWoodsBob]

Ah I see, so the breakout board makes it truly pnp?

[icingdeath88]

Originally Posted by BackWoodsBob

Ah I see, so the breakout board makes it truly pnp?

Very nearly, there are a couple things that will need separate wiring added, like the IAT sensor, wideband O2s, etc. But everything the stock ECU connects to would be pnp.

[BackWoodsBob]

Thanks for the info on that!

[BackWoodsBob]

Waiting till I get the rest of my parts car money and I'll be ordering a MS2 with a break-out board!

[icingdeath88]

Originally Posted by BackWoodsBob

Waiting till I get the rest of my parts car money and I'll be ordering a MS2 with a break-out board!

MS2 or MS3?

[BackWoodsBob]

ms2 with the adapter board. most likely anyway.

[BRZCory]

We demand more updates!

:angrymob:

[BackWoodsBob]

You demand? BUY YOUR OWN ><><><><><><>

[BRZCory]

Quick question, I've found a couple other people doing EG33+Megasquirt, did you attempt to just use resistors at all to clean up the signal, before you used the VR board?

Originally Posted by anotherForum

So I've learned how to finally get her to rev up to 8k. Seems like my cam signal had alot of noise in the line. So I had to place a 2.2k resistor from + to - then a 18k resistor in the + side of the line. this cleaned up my signal and 8k red line was achieved.

[icingdeath88]

Originally Posted by BRZCory

Quick question, I've found a couple other people doing EG33+Megasquirt, did you attempt to just use resistors at all to clean up the signal, before you used the VR board?

Yea I tried a few resistor combinations, those that reportedly worked for those with EG33s, as well as for EJs (2.0, 2.2, 2.5l), and none worked for me, but the VR board took care of it right away. What works for MS2s, and for the other various toothed wheel configurations of the EJs, is not guaranteed to work for the MS3 + EG33. The way the VR board works makes a lot more sense than the simple resistor/hysteresis tweaking that you're stuck with without it. I don't have the electrical background necessary to explain it; Harvey tried to before, and what I got out of it was that it ought to be overkill. The jbperf VR board is very similar to the circuitry used in the MS3pro, and the MS3pro is designed to have as much compatibility as possible with as many different VR sensors as possible. That said, I didn't try anything above 5k rpms.

As for updates, I don't have anything for you right now. The projects have progressed in a weird way so I'm kind of stuck without being able to work on the ECU stuff right now. However, I have already pretty much already documented everything needed for someone to get started with their own. Are there any more specific questions, like what BackWoodsBob has been asking?

[BackWoodsBob]

Originally Posted by BRZCory

Quick question, I've found a couple other people doing EG33+Megasquirt, did you attempt to just use resistors at all to clean up the signal, before you used the VR board?

When did you get an ms?

[BRZCory]

Originally Posted by BackWoodsBob

When did you get an ms?

About an hour and a half ago.



And thanks for your help, I'm sure I'll have more questions! Though mine is but a lowly MS2 and not the 3/3x. I imagine the VR2 board probably has some op amps and so on to first receive the lower-level "dirty" signal, filter it through an amp, and then output a nice clean waveform.

I have a few days of playing around with the megastim and getting used to the software before I actually head to the car. And I'm probably going to either cannabalize the spare ECU that I have, or buy a breakout board for swappability (Either option requires a bit of time though). I also need to get an IAT sensor still.

...and then, upgrades (bigger injectors, and, well, M90)...

Thanks!