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OK, back on topic - why do they want such accurate base cam timing when they have camshaft position sensors and can vary the timing? On my Fiat 1.4 there is only one true cam (exhaust) and it isn't variable. The intake is "virtual" and completely variable. So it makes sense why they'd want better control of the cam timing there, but it looks like the Ford 1.5 has both cams variable.
It appears that the camshaft position sensor gets a look at the cam once each revolution - it looks like there is a feature in the cam forging part way down the cam. My bet it that they get a good relative measure of cam angle, so that they can tell the difference between 10 and 12 degrees, for example, but I bet the absolute accuracy of the position sensor is not that good. The crankshaft position sensor is looking at a lot of teeth, it has pretty good resolution and accuracy. So I think that's why they still need the cam timing to be set accurately - they can't tell the absolute cam angle very accurately, they can only see it moving accurately, and they only get to look at it once a cam revolution.
BTW, not that it answers this question, but some interesting detail: https://www.team-bhp.com/forum/technical-stuff/191686-close-look-fords-new-1-5l-3-cylinder-dragon-petrol-engine.html
It appears that the camshaft position sensor gets a look at the cam once each revolution - it looks like there is a feature in the cam forging part way down the cam. My bet it that they get a good relative measure of cam angle, so that they can tell the difference between 10 and 12 degrees, for example, but I bet the absolute accuracy of the position sensor is not that good. The crankshaft position sensor is looking at a lot of teeth, it has pretty good resolution and accuracy. So I think that's why they still need the cam timing to be set accurately - they can't tell the absolute cam angle very accurately, they can only see it moving accurately, and they only get to look at it once a cam revolution.
BTW, not that it answers this question, but some interesting detail: https://www.team-bhp.com/forum/technical-stuff/191686-close-look-fords-new-1-5l-3-cylinder-dragon-petrol-engine.html