NA Crank Trigger Wheel Setup
#22
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Another day of failure.
I cut another tooth off the trigger wheel so it's a 12-1 wheel. I set timing to TDC and there was a tooth about a 1/4 inch (5 degrees) past the the crank sensor so I cut that one off. As I understand it, that made tooth #1 the next to reach the crank sensor, 25 degrees BTDC (360/12 = 30 degrees per tooth).
I cranked the motor over and got the exact same result as last time. Tach reads, then drops, syncs then drops. Then I started thinking I'd gotten the angle backwards. I'm thinking the 25 degrees was After TDC so I tried 335 degrees (360-25) as the trigger angle, which did the exact same thing. Still getting the same error code for the Loss of Sync, 2. Missing tooth at wrong time.
I cut another tooth off the trigger wheel so it's a 12-1 wheel. I set timing to TDC and there was a tooth about a 1/4 inch (5 degrees) past the the crank sensor so I cut that one off. As I understand it, that made tooth #1 the next to reach the crank sensor, 25 degrees BTDC (360/12 = 30 degrees per tooth).
I cranked the motor over and got the exact same result as last time. Tach reads, then drops, syncs then drops. Then I started thinking I'd gotten the angle backwards. I'm thinking the 25 degrees was After TDC so I tried 335 degrees (360-25) as the trigger angle, which did the exact same thing. Still getting the same error code for the Loss of Sync, 2. Missing tooth at wrong time.
Last edited by pdexta; 01-24-2014 at 06:21 PM.
#23
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Another day of failure.
I cut another tooth off the trigger wheel so it's a 12-1 wheel. I set timing to TDC and there was a tooth about a 1/4 inch (5 degrees) past the the crank sensor so I cut that one off. As I understand it, that made tooth #1 the next to reach the crank sensor, 25 degrees BTDC (360/12 = 30 degrees per tooth).
I cranked the motor over and got the exact same result as last time. Tach reads, then drops, syncs then drops. Then I started thinking I'd gotten the angle backwards. I'm thinking the 25 degrees was After TDC so I tried 335 degrees (360-25) as the trigger angle, which did the exact same thing. Still getting the same error code for the Loss of Sync, 2. Missing tooth at wrong time.
I cut another tooth off the trigger wheel so it's a 12-1 wheel. I set timing to TDC and there was a tooth about a 1/4 inch (5 degrees) past the the crank sensor so I cut that one off. As I understand it, that made tooth #1 the next to reach the crank sensor, 25 degrees BTDC (360/12 = 30 degrees per tooth).
I cranked the motor over and got the exact same result as last time. Tach reads, then drops, syncs then drops. Then I started thinking I'd gotten the angle backwards. I'm thinking the 25 degrees was After TDC so I tried 335 degrees (360-25) as the trigger angle, which did the exact same thing. Still getting the same error code for the Loss of Sync, 2. Missing tooth at wrong time.
ftfy
#25
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I'll agree that the 90-97 setup isn't as good since the cam signal is on a belt, but there's no reason to switch up a 99+ setup if you don't absolutely have to because the damper you are using is fixed with a really shitty wheel setup.
#27
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Yes but it is not used for ignition.
Take a timing light and see how much your actual timing wanders if you rev the engine? I can tell you that in my experience, the timing got a lot more stable after I switched to a trigger wheel.
BS. There's no proof that the stock sensors/wheels are any worse than 32-1 wheel setup.
I'll agree that the 90-97 setup isn't as good since the cam signal is on a belt, but there's no reason to switch up a 99+ setup if you don't absolutely have to because the damper you are using is fixed with a really shitty wheel setup.
I'll agree that the 90-97 setup isn't as good since the cam signal is on a belt, but there's no reason to switch up a 99+ setup if you don't absolutely have to because the damper you are using is fixed with a really shitty wheel setup.
#28
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I feel like I need to cut another tooth off the crank wheel but I hate to aimlessly chop up a $125 crank wheel hoping I get lucky enough to hit something that works.[/QUOTE]
Did any of the 36-1 threads help? The crank wheel is only 15-20 bucks. Either way, it looks like you need a CAS off the front. I got mine running with Soviet's help, major props for his knowledge.
Did any of the 36-1 threads help? The crank wheel is only 15-20 bucks. Either way, it looks like you need a CAS off the front. I got mine running with Soviet's help, major props for his knowledge.
#30
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How to make your trigger wheel work on MS3+MS3X with sequential injection and ignition
(assuming you wired your coils and injectors as fully sequential using MS3X board)
Part 1: Making your trigger wheel work
Part 2. Modifying and adding CAS, enabling full sequential
(assuming you wired your coils and injectors as fully sequential using MS3X board)
Part 1: Making your trigger wheel work
- Unplug the NA CAS/NB CAM sensor
- Make sure your trigger wheel has a missing tooth
- Figure out where the missing tooth comes in (e.g. angle)
Megasquirt-3 MS3 Trigger Wheel - Wire your crank sensor and mount the trigger wheel. The crank trigger has a single "signal" wire and that goes to MS3 trigger input (not MS3X)
- Change injection to "semi-sequential" (batch if not using sequential)
- Change ignition to "wasted COP" (wasted spark if not using sequential)
- Change ignition to "Single wheel with missing tooth"
- Try running the car. If it gets sync errors, you may have wired the crank sensor wrong. Or its too far away. Adjust until you have no sync errors and trigger log looks good.
- Verify the trigger angle with trigger light.
Part 2. Modifying and adding CAS, enabling full sequential
- Modify the cam signal so it only has one tooth
If your car is NA and you're using a CAS- Depending
- Take the CAS apart
- Modify your CAS to only have 1 tooth per camshaft revolution
If it's a "magnetic" cas and has metal rotors inside of it- You need to cut off all the teeth except one.
- A magnetic CAS has 2 rotors inside - one with 2 teeth and one with 4.
- I cut the 2 teeth rotor off completely, and 3 teeth off the 4-tooth rotor. I have pictures somewhere - it has to be a specific tooth that you cut off.
- Wire the CAS so only one wire goes to the MS3X "cam" input. Depending which disk/rotor you used inside the CAS you either use SGT (you used larger, 4-tooth disk/rotor) or SGC (you used smaller, 2-tooth disk/rotor)
- Change ignition settings to use CAM input. DO NOT change to sequential yet
- Try running the car and look at the log. If it runs but you get sync errors, your cam signal is probably wrong.
- Once you don't have sync errors, change to Sequential. It should still run.
so much informative your post, thanks for the clarifitacion.
I have a 1.6 Miata and i will mount a 36-1 trigger wheel with a NB2.5 crank sensor. I would like to use sequential injection (i think this is neccesary to run a crank sensor) and waster spark (because my Speeduino doesn´t support seq. ignition).
Could it be possible without remove any CAS teeth?
Thanks in advance
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