Battery compensation tables, specifically coil dwell table

[Simon P.]

Found some info here:
http://www.dtec.net.au/Ignition%20Coil% ... ration.htm
As per Lumley32's previous post, DTA coils drivers are clamped at 9A. No idea if DTA uses Bosch or other...
From the above website, to bench test a specific coil I'll need a coil driver. A quick search shows the Megasquirt crowed uses Bosch BIP373 for their coil drivers as they are cheap. rugged and easily available. Datasheet attached.
So a scope, a DC ammeter scope clamp, a DC power supply and a Bosch driver... List seems complete. If I can't find specific info antwhere else, I may just give this a shot.

[lumley32]

there is no real harm you can do, like Steve said its like filling a bucket! to be fair when i have done it i have used the bike but just unplugged the charging system and logged the voltage as it drops!!

[stevieturbo]

Found some info here:
http://www.dtec.net.au/Ignition%20Coil% ... ration.htm

If nothing else, that's a great website ! Lots of great info there.

[Jon K]

Found some info here:
http://www.dtec.net.au/Ignition%20Coil% ... ration.htm
As per Lumley32's previous post, DTA coils drivers are clamped at 9A. No idea if DTA uses Bosch or other...
From the above website, to bench test a specific coil I'll need a coil driver. A quick search shows the Megasquirt crowed uses Bosch BIP373 for their coil drivers as they are cheap. rugged and easily available. Datasheet attached.
So a scope, a DC ammeter scope clamp, a DC power supply and a Bosch driver... List seems complete. If I can't find specific info antwhere else, I may just give this a shot.

Good test Simon let me know what you find out. I run 2.6 - 2.8ms for BMW M50 bosch coil packs with no spark blow out up to 30 psi boost.

[Simon P.]

Jon,
Yeah, we're running 2.8ms on the stock Bosch S54 COP. Across the board with no compensations whatsoever. It seems to work (never had an issue) but someone got a peek at another ECU's map for the same engine and the numbers were quite different. Enough to get us wondering and into this whole "compensations" debate and the parallele "accessory underdrive" thread.
No hard data yet, some feelers have been sent out to various gurus and we're waiting on a bite.
I may try and drive the coil "manualy" by switching the current on briefly and looking at the scope trace rather than buy the Bosch driver. Might simplify the whole thing a bit... Right now my power supply is a no go as it's limited to 5A (thought is was a 15A, misread the label ).
I'll keep you posted if we get anything.

[Janoka2]

Some little information from my mesaurement .
The s50b32 bmw engine (in e36 car) in idle (battery 14v )coil time is 3200usec.
I mesaured with scope.

[Rob Stevens]

What are you measuring? the time taken for the voltage to peek?

[Janoka2]

I mesaure the factory ecu output and make a coil on with one factory ignition coil.
The value is 3200usec and this is the coil on time in s52b32 engine with good alternator that its make a 14 volt is running engine....
Every ECu make a ground when is the coil is on, this time is 3200usec (no voltage in output)...

[Rob Stevens]

ok, i should have said current to peak, i have no factory output to compare so I've set my coils at 3ms as the current has peaked then.