Hello all,

Continuing from my previous thread, I'm going to go with an MS-I v3.57 board running in parallel on my '99.

I have some free time coming up, so I'm going to tackle the install in about a week.

However, I'm still a bit unclear on the wiring. I've read Braineack's guide, but I'm still struggling with a couple of things.

First, how do I determine which leads on the boomslang should be wired to the megasquirt pigtail?

For example, I can see in the images on Braineack's guide that pin 37 on the DB37 connecctor is for the fuel pump, but I don't see where I get that signal from the '99-00 ECU pinouts.

Second, how do I wire the '94-97 CAS? I see pinouts listed on Braineack's guide. When I buy the CAS, do I need to get a wiring harness for that as well, and pass it all the way through the firewall to the megasquirt piggy?

 

Grab the 99 wiring pdf from http://www.madracki.com/miata/wiring.html and use that to get what pin number you need. Then use this diagram to find its position on the connector (most of the stuff you need is already marked anyways)



And dont bother with the cas...you can mod your stock crank wheel and use that.

 

You don't use the fuel pump wire when parallel.

Easiest route is to get the harness for the CAS from a 90-97 car but you can just connect small female spade connectors to the CAS pins. Then you run 1 wire to ground, 1 to 12v, and the remaining 2 to the corresponding wires on the DB37.

 

Ok, so if I use the NA CAS I do need to run the wires through the firewall. No prob.

Could you explain a bit about how you wired in the MSM in stages so you could monitor/test the MS before you gave it fuel / spark control?

 

Not much more to it than what you just mentioned. You just don't take the spark and fuel control away from the stock ECU (by not cutting the wires on the boomslang and redirecting them to MS). Make sure all the gauges read correctly and calibrate the TPS and such. After that, cut the wires over for injectors, then test it, then wires for spark.

 

Where is the rpm pin located? The pin out diagram I have does not have it listed right and the tps was not even on the right connector, Im trying to use an s-afc 2 for now until I get a Megasquirt. Just trying a budget build and Megasquirt is all i need now.

 

MegaSquirt gets it's rpm reading from the cam/crank trigger. i.e. the CAS on a MK1

 

well i should have just listened to everyone else and just gone mega squirt the s-afc 2 is junk ill put it on ebay for sale. maybe get me closer to a megasquirt.