Trackspeed 12+1 trigger wheel + VVT pulse pattern
#1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I'll park this here for posterity
Crank trigger wheel same as a Honda K20 (not same positioning though)
Crank trigger wheel has 12+1 teeth. Rising edge significant
- 12 regular teeth 30° apart
- one of the teeth are aligned to 10° BTDC #1/4
The extra (+1) tooth is at approx 30° ATDC #2/3
- This is ~10° after the regular tooth at 20° ATDC #2/#3
Intake cam trigger wheel
3 teeth; 2 are very close, and the 3rd is on the opposite side.
The trailing tooth of the double tooth is 180* from the single tooth
Sequence: (no matter what VVT angle)
TDC firing #1
single cam pulse
TDC firing #3
extra (+1) crank tooth
TDC firing #4
double cam pulse
TDC firing #2
extra (+1) crank tooth
cam rising edge locations at full retard:
80° ATDC #1 firing (single pulse)
40° ATDC #4 firing (leading pulse of double pulse)
80° ATDC #4 firing (2nd pulse of double pulse)
VVT max advance is 48°
As intake cam sweeps through phase range, the extra (+1) crank tooth never "crosses over" a cam rising edge
Crank trigger wheel same as a Honda K20 (not same positioning though)
Crank trigger wheel has 12+1 teeth. Rising edge significant
- 12 regular teeth 30° apart
- one of the teeth are aligned to 10° BTDC #1/4
The extra (+1) tooth is at approx 30° ATDC #2/3
- This is ~10° after the regular tooth at 20° ATDC #2/#3
Intake cam trigger wheel
3 teeth; 2 are very close, and the 3rd is on the opposite side.
The trailing tooth of the double tooth is 180* from the single tooth
Sequence: (no matter what VVT angle)
TDC firing #1
single cam pulse
TDC firing #3
extra (+1) crank tooth
TDC firing #4
double cam pulse
TDC firing #2
extra (+1) crank tooth
cam rising edge locations at full retard:
80° ATDC #1 firing (single pulse)
40° ATDC #4 firing (leading pulse of double pulse)
80° ATDC #4 firing (2nd pulse of double pulse)
VVT max advance is 48°
As intake cam sweeps through phase range, the extra (+1) crank tooth never "crosses over" a cam rising edge
Thread
Thread Starter
Forum
Replies
Last Post