I thought it would be a good idea to post some information from my build thread here so it would be easier to find.

More details on my build can be found here.
https://www.miataturbo.net/showthrea...205#post846205




I was originally fabricating my own 36-1 ignition trigger. This design used a wheel that brazes to the damper hub.










Then while doing some research on various Mazda engines I came across a 1.6L ZM-DE engine in a 2000 Protégé. The engine block looked remarkably close to a B6/BP so I did some disassembly to inspect. What I found is that the ZM-DE appears to share all the same dimensions with the B6 engine, except it has an aluminum lower split-block design and two extra oil drains on the exhaust side of the block/head assembly.

I then came across this while removing the lower timing belt drive gear from the ZM-DE engine.



I took and laid a 99’ crank trigger wheel I had over the top of the ZM-DE trigger wheel.







O.D. and the center bolt pattern appear to be identical!













I contacted my local Mazda dealer to get a part number and pricing.

#ZM 01-11-408
$21.68

 

Superb work!

 

Wow!! awesome!

 

surprised this didn't get more reactions. Seems like a very easy way to replace the 4 tooth wheel on a NB with a 36-1 wheel. Lots more resolution.

 

I have one and will be using it with MS3
Haven't 100% figured out the input mods but it should be straightforward.

 

I plan to get one later on as well

 

Thread stickeyd, and added to the MS "Super Important" list.

Thanks for the clever detective work, Matt. This is really phenomenal.

 

Thread o the month.

 

Brilliant detective work! Figured I'd add this to the thread, looks like the same part and the numbers match:

http://onlinemazdaparts.com/parts/20...icleid=1363777

OnlineMazdaParts.com - 2000 Protoge 1.6ltr / ENGINE / ENGINE & TRANSAXLE / ENGINE PARTS / Crnkshft pulley plate, ZM 01-11-408 (#2 in diagram) $12.36

I'll probably just order one to play with and confirm, I've got a few other little parts I need to order as well

 

Ordered one, and will report if the stock sensor reads it and communicates with MS3.

 

Received the part, diameter holes and slight offset as on original:



Installed and sensor should be able to read teeth





While I was checking fitness, I noticed that the missing tooth passes the sensor ~90 degrees before #1 cylinder is at top dead center.
Being new to Megasquirt,can this be handled in software or should the gap be at #1 Top Dead Center.

I'll be doing some reading tonight, but I thought it might be of interest to someone to get this out and open for discussion.

:edit: It appears that Megasquirt likes to have the missing tooth 9 teeth before TDC of #1. For 36 tooth wheel 9 teeth is 90 degrees, so I think the gap is right where it should be.
hrk

 

Nice, glad to see some confirmation. What vendor did you source it from?

In for "explain it to me like I'm 5 Hustler" instructions for setting this up in my DIYPNP

 

Yeah you can set it in software, see:

http://www.msextra.com/doc/ms2extra/...Miss_Tooth.htm

Just work out how many teeth between the gap and TDC and then work out your angle to plumb into the software

 

Looks like this place has it for 15 dollars
http://www.jimellismazdaparts.com/pr...ZM0111408.html
looks like around 23 dollars after shipping, for those who don't have a local mazda dealership.
didn't see the other for 12, dollars, oh well

 

so is there a full mazda part number for this? and will it work with a NA8C engine?
Here in the UK the mazda dealers don't like ordering parts unless full part number of VIN given,

Dan

 

Sub'd for this, need spoonfeeding please. Looks like an awesome upgrade.

 

Question about wiring to MS3 and sensor from -96. I believe my car has the original sensor from -96 donor, there is a bit of metal visible in the middle of the sensor as seen in the pitcure above and it appears to be magnetic, so I assume it is VR type. The wiring diagrams I have found so far show different color labes than the actual wires in the car.

Sensor has three wires at the connector behind 8" pigtail.
Red
Green
Black



And they connect into
cars wiring harness as
Red -> Green/Black
Green -> Green Yellow
Black -> Black/green

According to wiring diagrams there should be Yellow/Black and Yellow/White and Black/Light Green wires coming out from this sensor.

https://www.miataturbo.net/engine-performance-56/na-nb-crank-wheels-same-34986/

Black/Light green appears to be the ground shield in both original car and wiring diagrams. Two other wires disappear into original ECU pin 4E and 4H.
From internets I found names for these pins.
4E Crank miss-fire sensor N/U
4H Timing ground for crank pickup

I understand that VR type sensor creates voltage on its own, and that would make sense per original wiring diagrams.

The real question I am trying to get to is how to get this sensor connected to MS3 or MS3X?

Currently I have it wired like hall sensor:
+5v from Megasquirt throttle output to the Red at the sensor
signal ground to the Black shield wire at the sensor
Pin 24 on MS3 to the Green at the sensor.

I think it is not correct.

I am using DIY wiring loom and it has nice shielded wire for crank sensor which has tiny white and black wires.

hrk

 

Your car's wiring puzzles me. Is this a US-spec car, or is it from a different region?

At any rate...

You do not need +5 from the ECU with a VR sensor. One of the VR sensor's active wires will go to the ECU's VR input, the other will go to the ECU's ground along with the shield wire. You will need to experiment to determine the correct polarity (which one of the green wires goes to ground vs. which one goes to the ECU's VR input.)

 

From your description,
"4E" pin is wired to the white wire inside the shielded cable
"4H" pin is wired to the black wire inside the shielded cable
Black/green can be connected to ground or to the shield conductor on the shielded cable

As Joe pointed out, the sensor polarity as used on the stock computer *may* be backwards for the MegaSquirt. You have a 50/50 shot. You need an oscilloscope to determine this ahead of wiring. Without a scope, you can wire it up and use MegaSquirt's toothlogger function to determine if polarity is correct. If wrong, just reverse the wires.

 

Thanks guys,

The car is US spec -96, and this part of the wiring harness should be as it came from factory.
I had Emanage Ultimate there for ~5 years and now rewiring the whole thing for MS3. I never had to touch this part of wiring. Of course there is a chance that I picked wrong connector from the bundle of wires now laying on the floor, but it is one of the last connectors in the loom, relatively close to TPS and idle valve connector, and it fits physically. It has been a long week in the garage.

I will try one way, I presume there no danger of damaging the sensor or with the small voltage VR sensor puts out while cranking.

Thanks again, I will report how it goes. I think it will be very easy 36-1 conversion for NB Miatas with stock parts, once the wiring is figured out and the sensor can communicate singal to software.
hrk