Cranking dwell limit

[Reverant]

I have a stock car that has ~50ms dwell time when cranking (scoped), then it ramps down to 4.0-6.0ms after starting on the stock ECU.

I can only get up to 25.5ms with the MS3, and that's after I change the crank_dwell upper limit value from 8.0 to 25.5.

Obviously this being a U08, it can't go above 255, ie 25.5ms.

I would love to be able to go above 25, ie 50ms like on the stock car, just to see if it starts any better when completely cold.

Comments?

[slow_hemi6]

If you scope the coils current I am sure you will find it goes into saturation well before 50 mS even if that is what the factory uses for crank. Going beyond saturation is useless and very hard on the coils.

[thokes82]

It is indeed true that some cars deactivate dwell limiting (entirely) during cranking. I have never seen this really neccessary though.