why does my dwell spike to 9ms.???

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Tinkers Toy
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why does my dwell spike to 9ms.???

Post by Tinkers Toy »

Is this normal? I set the dwell to 3.5 ms. for my LS2 D585 coils with the built in heat sinks. Cranking dwell is set to 6 ms. I took a tuning ride today and when I was looking at the log I noticed the dwell jumped over 9 at some point. This surprised me and I'm not sure what is going on there and why.
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nathaninwa
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Re: why does my dwell spike to 9ms.???

Post by nathaninwa »

Look at battery dwell correction and battery volts at that point Even tho dwell is limited to under 4ms that typically at 14.2 volts, as volts drops dwell has to increase to maintain the same current.
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Tinkers Toy
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Re: why does my dwell spike to 9ms.???

Post by Tinkers Toy »

Thanks for the response. It makes sense now, I can't find battery dwell correction in MegaLogViewer but I see the relationship when the battery voltage drops off during cranking. I thought setting dwell to 6ms. compensated for the voltage drop but I see now that there is also additional compensation for low voltage at all times based on voltage. I get it now.

hey,fellow ls2 D585 coil users, where do you set your cranking dwell?
nathaninwa
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Re: why does my dwell spike to 9ms.???

Post by nathaninwa »

Mines at 6ms
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kjones6039
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Re: why does my dwell spike to 9ms.???

Post by kjones6039 »

Tinkers Toy wrote:hey,fellow ls2 D585 coil users, where do you set your cranking dwell?
I run mine a bit lower than Nate...... 2.5-3.0 seems to work well with my setup.

Ken
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kaeman
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Re: why does my dwell spike to 9ms.???

Post by kaeman »

I am running mine at 3ms. I have no problems with a weak spark.
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nathaninwa
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Re: why does my dwell spike to 9ms.???

Post by nathaninwa »

I've never tried a lower cranking dwell tbh. Matt had posted one time about using 6ms, as the duration and rpm become a moot point during cranking and some motors like a hotter spark
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Tinkers Toy
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Re: why does my dwell spike to 9ms.???

Post by Tinkers Toy »

I just didn't want to burn them up. It's just during cranking, looking at all the responses I'm sure it will be ok. Thanks.
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