Looking for analog inputs? (Can-bus expansion board?)
 

Currently busy installing an MS2 V3.0 on my RX7 FD, and I'm having troubles finding enough input pins. I'm obviously using the MAP, TPS, AIR temp, CLT temp and EGO1 inputs.
That pretty much leaves me with JS4, JS5, and EGO2

Now, the additional sensors I really want to add is a fuel rail pressure sensor, and 2 EGT sensors. If possible I would like to add in the knock sensor, and maybe an oil pressure sensor, and an additional MAP sensor for baro correction.

So, question one, I'm pretty sure I can hook one EGT input up to JS4, and the other one to JS5, but is it possible to hook the fuel rail pressure sensor up to EGO2? I can select it at generic sensor inputs in tunerstudio, but don't know if it will work, since I've heard about EGO2 using the same calibration as EGO1 (which I'm using for my wb lambda sensor)

Question two, With the MS2 V3.0 board, does anyone have any experience with hooking up a CAN-bus expansion board? I've found one that seems like it would suit the bill, but I'm not really sure of the MS uses an MS specific protocol, or a common one. I added a datasheet of the one I found, the baudrate, emission frequency and CAN ID's are user programmable.

Here is the datasheet:

Analog to CAN converter

I've been looking at CAN bus expansion boards for my MS3 Pro build and thought I was pretty locked in to building a GPIO box (GPIO Basic Kit DIYAutoTune.com). However, that Analog to CAN converter you posted looks perfect. I don't need all the extra function of the GPIO, just want more analog inputs.

Yeah I know, I also looked at the GPIO, because it's specifically made to work with the megasquirt, but for the task at hand it's soo complicated.

Here's a datasheet of the older version of the analog to can converter, I believe you can get the new version in the older case if you really want.

A-CAN-Dongle

The new version in the new case looks best to me.

Being from the US, I have no idea how I would get my hands on one though. Any ideas on price/availability/etc?

Never mind, I lied...the connectors required for the A-CAN-DG-V2 are $120....so I doubt that the unit will be a very cost effective solution. I sent out an email to the company anyway, so we'll see.

Just got a quote back from Texys on the A-CAN-DG-V2.....695 EUR. I bit cost prohibitive in my opinion....MS GPIO it is for me.

Wow, I asked for a quote, but didn't get a price yet. Indeed, too expensive.
I think I'll move expanding the amount of in- and outputs to the backburner, hook my 2 EGT sensors up to JS4 and JS5, and just try and see if hooking up a pressure sensor to the EGO2 input works or not.

TinyIOx v1.0 Board
This would probably suit your purpose(easily fit into the ms case) and the developer is a major megasquirt supporter on the megasquirtextra forum(i.e. this is specifically built for the ms2 in mind)...he also has a larger I/o board that isn't listed on the webpage but is on his forum...all this stuff you can find on the msextra forum no need to look elsewhere.

I looked into JBPerf's IOx boards (extended more-so than the tiny) and shared quite a few PM's with Jean. Purely functionally, it is better than the GPIO, but I really don't want to use the DB37 connector. Since I am going with the MS3-Pro ecu and will be using the 35-pin AMPSEAL connectors already and the GPIO kit that diyautotune sells uses the same 35-pin connector.

I know it sounds silly that I'm letting a connector dictate my decision, but that is the only negative I see about the IOx boards. The GPIO has slightly less features (still more than I will use) and has the good connector...therefore no real negatives for me.

If I was using a standard MS2 or MS3 and was already using DB37 connectors for that, then the JBPerf IOx boards would be my choice.

Another option would be to put the GPIO code onto a MicroSquirt, or a modified version of MS2/Extra for use as a CAN node. We're considering this on our land speed car, and we'll be sure to put together a how-to if we go this route.

Another thing to consider is that Jean is one of the ms2/extra developers. This means that the ms2/extra and ms3 firmware potentially work better with Jeans IO solution than with the GPIO board. We certainly work more closely with him.