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Wasted to Direct spark effect on Dwell times


Adturb

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My little brain has been thinking and I wonder if anyone knows the answer, I'm particularly think of the 4G63T engine and ignition setup. 

Lets say you start with a standard wasted spark system with 2 coils and the dwell at 14V is 5.5mS. 

You then install a wasted spark COP system and are told to set the dwell at 14V is 3.5mS, as per the coil's data sheet for direct fire use.

You then modify said kit to run in Direct spark and leave the dwell at 14V, 3.5mS. Now this is where I start to wonder about the dwell time, does the ECU reduce the dwell time to each coil, or has it unintentionally doubled because the coil is firing half as often? On the flip side should the dwell time be doubled when running in wasted as it's firing twice as often? 

Hope this makes sense, I guess the basis of my question is asking how the ECU applies the dwell in wasted vs direct spark. I would assume that in direct spark the coil sees the programmed dwell but is this the case in wasted?

I may have completely confused myself, if so, apologies. 

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The ECU will apply the dwell time from the dwell table regardless of ignition mode selected. So on wasted spark if the table had 3.5ms then each time the ignition drive activated (twice per two crank revolutions) it would have a pulse of 3.5ms. And if on direct spark if the table had a value of 3.5ms then each time the ignition drive activated (once per two crank revolutions) it would have a pulse of 3.5ms.

Regards.

Scott

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