Ignition cuts for rev limits / traction control

[Murphy, Ian]

Does anyone have any cunning ideas for implementing ignition cut strategies
for rev limits and traction control purposes?

I'm struggling with the following concern: You detect an over-rev (or
wheelspin) event and want to cut spark ASAP, but the coil driver(s) are
already charging the coil(s) for the next combustion event (or 2, or 3,
depending on your system). Do you wait until the next available 'slot' when
you can avoid charging a coil up (and therefore possibly risk over-reving
further) or can you 'bleed down' the charging coils somehow without causing
a spark to fire?

The only other solution that springs to mind is retarding the already
charging coils to limit torque output while waiting for the cut to be
available.

Another thing that bothers me is engine stalling: If you stall an engine,
and have a charging coil, what do you do with the spark? If you just fire it
off after the maximum safe dwell for your coil, the engine could be in any
position and you could blow up your inlet manifold, or push the engine
backwards...

Any thoughts?

Ian
----------------------------------------------------------------------------
To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org