Slow Monster rebuild

[Dukedesmo]

Originally Posted by Mr Gazza

Okay so the problem here is interference to the ECU from the coils, yes?

Mine has ignitech ignition/ECU and I was getting inconsistent ignition timing at idle (maybe elsewhere also but not so noticeable?) presumably due to the HT lead to the rear cylinder passing by the lead from ignition pickups to ignitech as they (must) cross to reach their objective.

I 'diverted' said ignition lead the other side of the frame rail and got it as far away as possible from the HT lead and the idle was noticeably smoother, as evidenced with a strobe on the flywheel now showing a (fairly) steady spark which, before was all over the place.

[Mr Gazza]

Originally Posted by Dukedesmo

Mine has ignitech ignition/ECU and I was getting inconsistent ignition timing at idle (maybe elsewhere also but not so noticeable?) presumably due to the HT lead to the rear cylinder passing by the lead from ignition pickups to ignitech as they (must) cross to reach their objective.

I 'diverted' said ignition lead the other side of the frame rail and got it as far away as possible from the HT lead and the idle was noticeably smoother, as evidenced with a strobe on the flywheel now showing a (fairly) steady spark which, before was all over the place.

So as well as sending a signal pulse from the crank sensor, the ignition cable was getting a (very slightly) delayed pulse via RF (or electro-magnetic radiation) from the HT lead.. Like an echo in fact.