Dwell timing for 350z coils

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sr Vegas 240
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Joined: Fri Mar 15, 2019 10:51 am

Dwell timing for 350z coils

Post by sr Vegas 240 » Sat Jul 27, 2019 7:15 am

So i have 350z coils on my s14a sr20det with ignitor deleted. 350z guys run 5.00 to 5.5 ms of dwell. How would i change that on nistune. I see the dwell time/duty table but i dont know what values to enter.
Here is what i found guys on PFC using for 5.00001 ms dwell time

IGN Dwell vs Time

Time = 166.6667 x angle ( / ) <-- that means divided by RPM

so here are my numbers for a 5.0001 ms dwell

RPM------------------Stock--------------modified for 5.0001 ms of dwell

10000 -----------------101----------------------------300
8000--------------------82-----------------------------240
4000--------------------43-----------------------------120
2000--------------------24------------------------------60
1000--------------------14------------------------------30
48------------------------9-------------------------(left alone)

Would i just enter the values on the right into the dwell time RAW table?

sr Vegas 240
Posts: 13
Joined: Fri Mar 15, 2019 10:51 am

Re: Dwell timing for 350z coils

Post by sr Vegas 240 » Sat Jul 27, 2019 8:07 pm

Not sure if im doing this right but here is what i did i took the 350z dwell 5.0ms/stock sr20 dwell 1.9ms( Can someone verify this is correct)
comes to 2.63 than i multiplied the stock value and came up with this. Is this right?
nistune dwell.jpg
nistune dwell.jpg (556.55 KiB) Viewed 228 times

Matt
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Re: Dwell timing for 350z coils

Post by Matt » Mon Jul 29, 2019 11:28 am

I thought stock SR20 dwell was something around 4ms from memory. so it only needs about 10-20% increase in percentage to increase dwell time

There is also an estimated dwell parameter you can select (right click gauges) in some ECUs

sr Vegas 240
Posts: 13
Joined: Fri Mar 15, 2019 10:51 am

Re: Dwell timing for 350z coils

Post by sr Vegas 240 » Mon Jul 29, 2019 5:57 pm

From what i searched i only saw 1.9ms.

Matt
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Re: Dwell timing for 350z coils

Post by Matt » Wed Jul 31, 2019 12:21 pm

Okay. Page 53
http://nistune.com/docs/Nistune_Mapping_Guide.pdf
Approx 3ms is what I measured on a number of ECUs

Also I scoped it another time back Aug 2016 for a customer to double check which was 3.5ms. See attachment
Dwell Coil settings.pdf
Dwell setting investigation
(609.25 KiB) Downloaded 12 times

sr Vegas 240
Posts: 13
Joined: Fri Mar 15, 2019 10:51 am

Re: Dwell timing for 350z coils

Post by sr Vegas 240 » Wed Jul 31, 2019 3:53 pm

Awesome that's some good info.
So going to 5ms from 3.5ms I would multiply current values by 1.42?

Matt
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Re: Dwell timing for 350z coils

Post by Matt » Sat Aug 03, 2019 1:29 am

Seems about right. 3.5ms to 5ms you mean?

sr Vegas 240
Posts: 13
Joined: Fri Mar 15, 2019 10:51 am

Re: Dwell timing for 350z coils

Post by sr Vegas 240 » Sat Aug 03, 2019 6:42 pm

Yes
Thanks

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