Might be a really daft question but here goes...

[fingersnfumbs]

So, as per a few previous posts Im converting my N/A Cosworth escort mk2 to throttle bodies.
Obviously going to need a crank sensor.
Now I know loads of places do a toothed wheel kit for a pinto which i assume will fit Cosworth but its a bit tight around the pully due to anacillary belt pulley and truth be told I dont really like the idea of a sharp tooth wheel wuring round there much. It could get really nasty if a finger strays while the engine is running or even a stone or something getting in there.
So...I had the idea of just tapping the alloy bell housing cover and putting a magnet on the flywheel. surely more acuarate being a bigger diameter too.
Has anybody done it?
Would it work?

[Graham]

the engine management system needs to see multiple pulses and a gap, which is why most trigger wheels are 36-1 or 60-2 tooth pattern. one single magnet isnt good enough. that would only get you one pulse per rpm. i have done engines that use a lumenition eye in a locked distributor as a trigger, but again its not really the way to do it as you still only get 2 pulses per rpm.

i think you are overly worrying, the teeth are not big enough to trap a finger even if you poked the trigger wheel with the engine running unless you have fingers the size of a baby

[katana]

the engine management system needs to see multiple pulses and a gap, which is why most trigger wheels are 36-1 or 60-2 tooth pattern. one single magnet isnt good enough. that would only get you one pulse per rpm. i have done engines that use a lumenition eye in a locked distributor as a trigger, but again its not really the way to do it as you still only get 2 pulses per rpm.

Not necessarily true! The crank wheel doesn't need a gap IF there is a cam sync trigger fitted. The ecu can work out where it is in the cycle and where #1 cyl is to either
provide a wasted spark style ignition / injection or fully sequential on both. I've managed to get a 4 cyl bike engine running with a 4 tooth crank wheel and a single tooth
cam trigger - it worked but not recommended LOL!
Problem with flywheel ring gear is the tooth count MUST be equally divisible into 360 or it won't work and most have weird tooth counts so its unlikely to work.
A 36-1 tooth wheel for a pinto / Cossie pully is pretty well protected and would need rocks to disturb it - see pic for idea

[Graham]

Not necessarily true! The crank wheel doesn't need a gap IF there is a cam sync trigger fitted.

yes, im aware, early bmw motronic used two sensors, one read the ring gear teeth and a second sensor to read an additional single TDC tooth

[3.5cologne]

Another option is to run a tooth wheel in the distributor. https://www.stinger-performance.com/...O1rXYDCtFBISlE