I revisited the thread tonight to catch up, and finally read the link in the second post pointing to chevythunder. I couldn't help but stumble several times on the description of the degree wheel.
Uh, no. Your math is bass ackward. It is true that the camshaft rotates once per two crank revolutions, but if the outer wheel has 360 slots it's only seeing 360 / 2 = 180 per crank revolution. Let's not get caught up on rising and falling edge signals here, but looking past one's interpretation of "pulses" it's getting 360 signals per crank revolution or 720 signals per cam revolution, max.Originally Posted by (chevythunder page)
This statement is only correct if you consider "pulses" as both rising and falling edge, but why would we be thinking in terms of camshaft revolutions? As a person who's on the Asperger's spectrum, this drives me batty.Originally Posted by (chevythunder page)
Unless vilefly beats me to it, I'm thinking my game plan for winter is giving the arduino a shot with the assumption of driving ls1 coil modules with 5v ttl signaling. I think this can be done without looking at the high resolution signal by keeping memory of the current position and calculating rotational speed based on the smaller of the lower resolution signals which the aforementioned page says are signaling 1,4,6 and 7. Another presumption I think can be relied on is where the crank comes to rest at engine shutdown. I've learned from talking to some white haired gentlemen who've seen their share of missing flywheel teeth that chevy v8s tend to come to rest in only about four different spots. In a case of the crank being jogged by a mechanic, if we assume the ECM follows the same logic, worst case the uC will miss the first or second cylinder firing after a power loss but so will the ECM with injection sequencing.
Am I making any grotesque oversights?
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