Syvecs Forums

Hi,

I am getting very frustrated trying to achieve what I thought would be a simple process to get sync on my BMW S14 engine.
I have the following settings:
I have a 24-1 tooth trigger wheel on the crank and a single tooth on the cam for sync so single gap single cam setup.
Therefore number of teeth = 23
Number of crank tooth gap definitions = 23
Crank tooth gap widths: 15,15,30,15,15 continued
Crank tooth gap minimum widths: 12,12,24,12,12 continued
Crank tooth gap maximum widths: 19.5, 19.5, 39. 19.5, 19.5 continued
Crank tooth gap repeats: All 1's

WRT sensor settings
For crankshaft position sensor:
Sensor type for VR sensor = 5V Bipolar
Input Filter = OFF
High trigger Threshold: 2v across all
Low trigger Threshold: -2.5v across all
Signal trigger edge = falling as that is the steepest

Cam Sensor:
Type is again 5V Bipolar for another VR sensor
Input filter = OFF
High trigger Threshold: 1.0V across all rpm
Low trigger Threshold: -0.5v across all rpm
It appears to pick up the teeth but when it comes to the cam ref signal it tries to sync but then only picks every second tooth...

Any ideas would be much appreciated

Thanks

upload the cal.

And a log of cranking too to see what syncstate is is saying etc

Thanks

This was the log

That isn't a datalog, but it seems it isn't happy with both crank and cam.

A proper datalog will give more info ( as well as the synclog )

Try this, I'm certainly no expert at this, but this would make it more comparable to my 36-1 which works perfectly in a similar configuration. Certainly your waveforms are very strong so no problem there.

Thanks. I'll try that layer on when I get yo.my workshop...
I'm curious to know what you have changed other than disabling the gap validation?

changed gap tooth widths, validations, trigger thresholds

Ensure to recheck base timing if/when it runs

As said, it's close to what I've used on 36-1 triggers without issue. Obviously some parameters are different because of different tooth counts.

Thanks for your input, much appreciated however it still has some issue with recognising the cam signal...
If you look at the synclog attached the red lines indicate it is happy and recognising each tooth and the gap but when it gets to recieving the signal from the camshaft it then draws green lines after every second crank trigger gap rather than every single gap...

Any more ideas?

Again, post a datalog.

And are your tooth position references correct ?

Without a cylinder 1 tdc reference Vs crank/cam I cannot see if these are right.
Pressure sensor in cyl1 is ideal.

And are you saying the engine does or does not run ?

It should still be capable of starting in 360.

You also have min engine speed for 720 sync set at 1000rpm.

So it's never going to do it at cranking speed.