Miata Crank Pulley, WTF is the story here?
#1
Miata Crank Pulley, WTF is the story here?
So i've looked all over and seen conflicting answers to this. I know alot of guys here run the supermiata damper on the 1.8 motor so I'm looking for an answer to put my brain to rest.
My car is a '92, and I'm putting in a built 1.8 from a '96. I believe I have my timing set...verifying the timing marks on the cam gears are right, first lobe on the intake cam is pointed 9 o'clock and the first lobe on the exhaust cam is point 3 o'clock, 19 teeth between the top marks on the cam gears, and the lower crank gear "half moon" pointed up at the arrow on the oil pump. I'm about to put my supermiata damper on, so I marked the two notches on the damper with orange and white paint as seen in the pics.
My confusion is that the left mark lines up with the "T" TDC mark, and the second notch to the right is off the scale. On most of the two notch dampers I've seen, it has the left notch at the left 10 BTDC and the right notch at T. I've heard that it's different on 95 motors, 96/97 is the same as 94, etc etc.
The last pic is me placing the OEM damper up there so you can see that the two notches on that damper also reside in the same location as they do on the supermiata.
So what's the story here? Are those notches where they should be? I have a feeling like once the car is started then you would modify timing to get the orange dot at 10 and the white dot at T....does this sound right? If I fired the car up would i see the orange mark reading on the scale to the left near 10, or would I have to assign a fixed timing value in tunerstudio to set base timing?
Here's a link i found around this question, but it's the only one i could seem to dig up. http://www.mazda-speed.com/forum2/in...c,26758.0.html
Thanks in advance.
My car is a '92, and I'm putting in a built 1.8 from a '96. I believe I have my timing set...verifying the timing marks on the cam gears are right, first lobe on the intake cam is pointed 9 o'clock and the first lobe on the exhaust cam is point 3 o'clock, 19 teeth between the top marks on the cam gears, and the lower crank gear "half moon" pointed up at the arrow on the oil pump. I'm about to put my supermiata damper on, so I marked the two notches on the damper with orange and white paint as seen in the pics.
My confusion is that the left mark lines up with the "T" TDC mark, and the second notch to the right is off the scale. On most of the two notch dampers I've seen, it has the left notch at the left 10 BTDC and the right notch at T. I've heard that it's different on 95 motors, 96/97 is the same as 94, etc etc.
The last pic is me placing the OEM damper up there so you can see that the two notches on that damper also reside in the same location as they do on the supermiata.
So what's the story here? Are those notches where they should be? I have a feeling like once the car is started then you would modify timing to get the orange dot at 10 and the white dot at T....does this sound right? If I fired the car up would i see the orange mark reading on the scale to the left near 10, or would I have to assign a fixed timing value in tunerstudio to set base timing?
Here's a link i found around this question, but it's the only one i could seem to dig up. http://www.mazda-speed.com/forum2/in...c,26758.0.html
Thanks in advance.
Last edited by OGWar; 06-23-2016 at 11:48 PM.
#5
I was curious of this too, thanks everyone.
On a somewhat related note - the crank trigger wheel has it's missing teeth like 60 degrees counter-clockwise of TDC, is that correct? or did I manage to put it on wrong? I checked at least 3 times and it only seemed to fit one way - but I'd like to be sure.
On a somewhat related note - the crank trigger wheel has it's missing teeth like 60 degrees counter-clockwise of TDC, is that correct? or did I manage to put it on wrong? I checked at least 3 times and it only seemed to fit one way - but I'd like to be sure.
#6
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The absolute position of the missing tooth doesn't matter, only the relative position of the missing tooth as compared to the crank sensor. This is all adjustable in software, but in general, you want the missing tooth to pass under the sensor no less than 50-60° BTDC. And I can't remember where the sensor is on a '96 engine (I assume you're using the OEM sensor).
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