MS3, MS3x, for a 2002. What to buy?
 

I'm going to buy the kit and start building my MS3 on my desk here, do I need anything besides the build kit and the MS3x? I don't have a stim, so I'm guessing I should get one of those as well? I just remember there being a few extra things to buy when I did the MS1 in my '94.

Now I will go read on the megasquirt forums so I don't have to ask too many stupid questions here as I'm building it.

Holy crap, the JimStim is expensive, and there aren't any used ones on ebay. Wouldn't people sell them when they're done installing the MS in the car?

I have one, your welcome to make me an offer via PM on it.

Parts to make Joe Perez's spark circuit. (MS3x still does it wrong)

Does it? Braineack and Y8s are both running full sequential with the MS3x controlling spark and it works. My car should be working shortly on it.

No it doesn't, MS3x does it the same as uS which is the 'correct' way.

So it sounds like I only need the MS3 kit, the MS3x, and a stim?
It looks like the MS3 comes with a plug to make a wiring harness, but I can't tell if the MS3x does or not. Does anybody know? If I can find the miata plug somewhere, I will try to build the harness myself.

There is no need to do "Joe's Spark Circuit".

When you buy the MS3 kit and MS3x, they come with the DB37 connectors you need to make a harness. Talk to y8s about the mazda ECU connector, I think he has a spare.

The Input Circuit you DO need to add is this one outlined here: http://westfieldmx5.devocht.com/index.php?section=35
see Step 50.

You will also need to do the alternator control circuit outlined above.

Also very little needs actually be populated on the mainboard, so save yourself the trouble when building it and omit the circuits that are pointless. It should also be outlined on the build thread linked above.


Don't follow any other "additional/optional circuits" or the step 65.

skidude, I have an MS3+MS3X+alternator controller+A/C controller etc etc for any 01-05 ready and tested on the stim but not on the car. It would save you A LOT of trouble if you are to buy it ready and tested working instead of building it from scratch. PM me if you are interested in it.

There is a DB37 included for the main board, but the MS3X DB37 is sold separately (we figured most people would be buying the harness anyway).

Joe's spark circuit would only be of use if you were using the main board spark outputs; I see no point in doing that if you have an MS3X. The MS3X outputs go low when powered up until commanded to spark; there isn't any chance of a pop when you turn the key on.

I've burned all sorts of firmware on my MS3X and never disconnected anything...

This, I didn't notice and spent a couple days desperately searching for a db37 that I thought I saw, and assumed I would have received :)

I assume I still need a GM IAT and that open is better? That's the one I used on the last setup, and I didn't bother with a bung, I just drilled and tapped the charge pipe. Seemed to work alright, though sometimes it would act like it heat soaked when I came out from grocery shopping.

Yes, just need an open GM IAT.

How about the DB9 tuning cable? The MS3 has USB support, right? Does that mean I don't need the special tuning cable?

Stims still here, I did not hear back from you on it.

You can use a serial cable, or a USB cable. You just need one of the ones that printers use.

You should have a PM or two on it.

I've got the MS, and I've started building. I just got to step 50, and I wanted to make sure I'm reading the schematic right... all the resistors and stuff I need is already in the kit, right? This picture shows in green what would normally go there, and in gray what I'm installing, right?

And for future parts, do I need any pieces that didn't come with the kit?

Edit: The green dotted lines I need to add, I know this.

The TL082 doesn't come with the kit.. nor do many of the resistors and capacitors for Frank's circuit you linked. He does have a parts list on his site.
http://westfieldmx5.devocht.com/inde...on=35&page=102

For the NB Alternator control, you need to verify 100% that it works before installing it. This can be done with a multimeter and a variable power supply that goes from about 10-16V. It must be verified to hold the setpoint between 14.1 and 14.3 or you will either fry your ... well everything electrical... or never charge your battery.