OrangeRoadster

Thanks to Aussie Driver for the msq file!
I got the car up and running (MS fuel only) fairly easily and cruising around the neighborhood it already drives very well.
I upgraded to the 08f high res code and had already done the wheel decoder mods. I found that everything worked nicely with the MS sharing the primary CAS rpm signal, but I could not share the secondary signal without causing a stall/no start.
******The MS recognizes the rpm and adds fuel appropriately without the secondary signal, but I'm sure I will need it when I do spark.******
EDIT: IT IS THE STOCK ECU THAT IS NOT CONNECTED TO THE SECONDARY SIGNAL. THE MS IS CONNECTED TO BOTH. SEE BELOW.
After some initial tuning, I found my values were very similar to saboteur's numbers from the settings thread
https://www.miataturbo.net/forums/showthread.php?t=3077
So I redid the untuned parts of my VE chart based off of saboteur's chart and was consistently around 13 or 14 to 1. I used autotune to tweak the values, and that seemed to work nicely. The idle is ok and the car starts fine from 65F temp. Driveability is comparable to the stock ecu, and I haven't even tweaked anything but the basic fuel map. Intake air temps are quite high, so I'm looking forward to rerouting the intake away from the header. Next, I'll do the spark mods to the board.

'90 w/'99 engine. MSNSe 08f high res. Fuel Only right now.

kingofl337

You shouldn't have a problem sharing both signals with the ECU.

OrangeRoadster

Thanks. I guess that means there's probably something wrong with my board... I'll check it out soon.

MiataMath

I had the same problem with sharing the 2 CAS signal with my stock ECU. I was able to get it worked only sharing the primary signal, but wouldn't start with the 2 signal.

Not sure what was the problem, I don't have my MS anymore.

Do a search for my old success story and you will find some more info.

OrangeRoadster

Well, it was a week ago that I wired this up and I just took another look at the wiring. My description was incorrect. The MS is wired into both rpm signals. It is the stock ecu that does not have the secondary rpm signal (black/white) and will stall the car if connected. I measured the voltages vs ground on the primary ~3volts, and the secondary ~1.1volts. The stock ecu outputs 14volts on the cut black/white wire exiting the ecu.

McKirkus

So is it correct to assume you don't need the earlier CAS installed if you're using a '99 or '00? (pre VVT)
EDIT: Megasquirt is in the mail. Going to Squirt and Spark my stock '99.

kingofl337

The 99 hasn't been installed before. But Reverant was having a hard time getting 4 clean pulses out of the crank sensor. So he installed a 94-97 cas.
I am going to install a MS on my 99 someday but I haven't had time. I also need to get my COP setup finished first incase I pop the 99 coils.

OrangeRoadster

I'm using a '90-'93 CAS. I don't have the one from the '99 and don't know.

McKirkus

Reverant said: "I have ordered an MS for my '02, 1.8lt VVT 6-speed."

He has a VVT engine ('01+) which has reportedly been the cause of some issues. So I'll let you guys know if that was the issue in the near future.

Sorry to hijack your thread, congrats on making progress OrangeRoadster

kingofl337

Your not listening/reading the CRANK sensor is giving off an extra two pulses on the 99+ cars. VVT has nothing to do with the crank sensor.

Reverant

iTrader: (10)

That would be the CAM sensor. The crank gives 4 nice pulses. The cam gives 1 pulse on the first 180 degress of rotation, and 2 pulses on the next 180 degrees. Also, the pulses on the cam sensor are inverted, ie a constant 5V that is pulled to ground when the trigger passes in front of the sensor.