Mazda MX5 NB2 (VVTi) with 36-2 trigger wheel

[castillaricardo]

Hi all. I'm gathering information to swap a Mazda MX5 NB2 VVT engine into my NB1, and I would like to run a 36-2 crank trigger wheel. Does the G4X support this configuration? If so, could you show me how to properly configure the trigger settings?

Thank you,

Ricardo

[Adamw]

Set triggermode to Mazda MX5 NB 36-2 should be all you need to do.  The trigger offset should be in the ballpark if your 36-2 wheel was made by flying Miata, if it is from some other company then likely not.   Regardless it needs to be checked with a timing light.

For the VVT, set it to MX5 VVYi mode assign the input to trig 2 and the correct aux for the output.  Warm the engine up, hold it at about 2000rom and set the cam angle test to calibrate, it should turn itself off after a few seconds if successful.  

 

[Vaughan]

My trigger offset is -9 for a skidnation 36-2 with the gap clockwise from the locating peg when looking at the front of the motor from memory

[castillaricardo]

Awesome. Thank you both for the information. I'm going to install a Supermiata 36-2 trigger wheel and the missing teeth seem to be in the same place as the skidnation one, so it should be around the same as yours. 

[castillaricardo]

@Vaughan any chance you could double check your trigger wheel has the gap on the intake side when at TDC? The ECU has sync when cranking with Fuel off but my timing light isn’t working again. I’m going to borrow a timing light in a couple of days but would like to know the offset is in the ballpark.

 

[Vaughan]

All pictures taken with the crank in the same position

[Electredge]

8 hours ago, castillaricardo said:

@Vaughan any chance you could double check your trigger wheel has the gap on the intake side when at TDC? The ECU has sync when cranking with Fuel off but my timing light isn’t working again. I’m going to borrow a timing light in a couple of days but would like to know the offset is in the ballpark.

 

has this run before on the Link ecu? if not can you post up the current map and log of cranking, maybe something else is wrong

[Adamw]

Also if you are running COP you should try adding or subtracting 360 from your offset. 

[castillaricardo]

1 hour ago, Electredge said:

has this run before on the Link ecu? if not can you post up the current map and log of cranking, maybe something else is wrong

My map is here: https://1drv.ms/f/s!Amu_1gWOWFlvmziL60snegeHxf7M?e=E3iobc

The car ran with the stock 4 tooth trigger. I just changed to a 36-2 yesterday but haven't started the engine because the timing light isn't working well, so I don't know if my offset is correct. Since the trigger wheel is similar to Vaughn's I'm going to assume the offset is close, or 360 degrees out, please let me know if my assumption is wrong.

This is still on the NB1 engine and it runs sequential COPs, which is complicating things a little. I didn't worry about taking a scope log because the triggers synced as I cranked (with Fuel set to off), but could take one tomorrow if I still can't get the new timing light to work. Thanks for willing to assist.

3 minutes ago, Adamw said:

Also if you are running COP you should try adding or subtracting 360 from your offset. 

I did try 0 and 360 offset, but neither showed the timing mark. I will try again tomorrow. Thank you!

[Vaughan]

Can you take a trigger scope? given your trigger wheel is a different brand to mine maybe it has the gap in a slightly different spot

[castillaricardo]

Sure. Here is a trigger scope and log of it cranking this morning: https://1drv.ms/f/s!Amu_1gWOWFlvmzvylI-WYSu8K6wN?e=pMfFJx

[koracing]

Have you tried moving the offset by 20 deg at a time and seeing if the timing mark shows up with the light?  I don't know if that trigger setup is using the gap in the crank gear to start counting offset or if it uses the trig 2 sync single or dual teeth for the reference angle, so I have no idea which way the offset should go to give the proper alignment.

[Electredge]

1 hour ago, castillaricardo said:

Sure. Here is a trigger scope and log of it cranking this morning: https://1drv.ms/f/s!Amu_1gWOWFlvmzvylI-WYSu8K6wN?e=pMfFJx

I would definitely already be doing what koracing just said above, but I have done a few of these and my offset is 70.

[castillaricardo]

58 minutes ago, koracing said:

Have you tried moving the offset by 20 deg at a time and seeing if the timing mark shows up with the light?  I don't know if that trigger setup is using the gap in the crank gear to start counting offset or if it uses the trig 2 sync single or dual teeth for the reference angle, so I have no idea which way the offset should go to give the proper alignment.

I haven’t but will do once I rule out my timing light as a problem later tonight or tomorrow. Maybe Vaughan or Adamw could answer what the reference point is.

 

6 minutes ago, Electredge said:

I would definitely already be doing what koracing just said above, but I have done a few of these and my offset is 70.

Thank you. I’ll certainly do as recommended when I get a chance.

[Vaughan]

comparing your trigger scope against my vvt motor and your cam is maybe 10deg off from mine

I would say turn the fuel back on and try and start it, did your timing light work when using ignition test? I assume you have the timing light clamp over an ignition lead between one of the coils and the spark plug?

[Adamw]

I just had a look at your log and was going to tell you your MAP sensor calibration was wrong, then I noticed BAP is the same.  The altitude runtime says you're 7400ft above sea level...  That's one I dont see too often.  

[castillaricardo]

8 hours ago, Vaughan said:

comparing your trigger scope against my vvt motor and your cam is maybe 10deg off from mine

I would say turn the fuel back on and try and start it, did your timing light work when using ignition test? I assume you have the timing light clamp over an ignition lead between one of the coils and the spark plug?

The car runs! The offset seems to be -8 for me, but I need to retest once the battery is properly charged. It seems I drained it in a bad way cranking this much. About the timing light: Yes, I put a spark plug wire between the coil and plug and clamped the light to it. Using an older timing light worked no problem, so mine is no good.

1 hour ago, Adamw said:

I just had a look at your log and was going to tell you your MAP sensor calibration was wrong, then I noticed BAP is the same.  The altitude runtime says you're 7400ft above sea level...  That's one I dont see too often.  

Yep, that's the correct altitude here. A drive around here sees anywhere between 5,350ft and 10,300ft in one sitting!

[castillaricardo]

Good thing I double checked. My offset turned out to be -24 and not -8! We can call the 36-2 install complete, and I'll get that NB2 motor installed in a couple of months. Thank you all for your assistance!