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Old 11-21-2011, 05:11 PM   #1
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Default MS3 setting dead time howto

I've seen the thread on how to experimentally determine dead time. This requires a running vehicle, which I don't have yet

I have ID1000's. They come with a dead time chart. How do I determine the values that go in the graph points of injector deadtime/pwm ?

For ID1000s the deadtime (in microseconds) is
psi 8v 10v 12v 14v 16v flow
43.5 2600 1675 1240 990 805 1015 cc/min

Be gentle - I've spent all day getting nowhere on this car. Not even a pop.

This is what I have for files so far...
Attached Files
File Type: msq CurrentTune.msq (130.7 KB, 67 views)
File Type: msl 2011-11-21_15.27.55.msl (50.8 KB, 59 views)
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Old 11-21-2011, 05:54 PM   #2
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are you sure that 12v # is correct?

go to injector characteristics. I think it asks for deadtime at 14v, so put in .805

then convert the rest to % from that number and alter the correction curve to match -- where 14v would be 100%.

if they want the deadtime at a different voltage, skew as needed.
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Old 11-21-2011, 08:41 PM   #3
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I thought it asked for deadtime at 13.2v I need to doublcheck tunerstudio
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Old 11-21-2011, 09:09 PM   #4
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(Sent from phone via capitalism)

TThat's probably correct. I was too lazy to look
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Old 11-21-2011, 09:13 PM   #5
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Braineak - I think the 12V number is ok.

ID1000 Dead time

43.5 psi
8V --> 2600 us
10V --> 1675 us
12v --> 1240 us
14V --> 990 us
16V --> 805 us

@45 psi

8V --> 2720 us
10V --> 1705 us
12V --> 1295 us
14V --> 1000 us
16V --> 810 us

If deadtime is at 14V, then I'd set the value to 990 us or 805 us?
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Old 11-21-2011, 09:37 PM   #6
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The deadtime is specified at 13.2V. So one linearly interpolates the value like this?

12V --> 1240us
14V --> 990 us

slope = m = (990 - 1240)us/2V = -125 us/V

y = mx + b

990 us = -125us/V * 14V + b = -1750us + b

b = 990 us + 1750us = 2740 us

therefore DT = -125us/V * V + 2750us

DT @ 13.2V = -125us/V * 13.2V + 2750us = 1100 us

Then I scale the other values to 1100 us?
Like
8V --> 2600 ---> 2600/1100 = 236.4%
10V --> 1675 ---> 1675/1100 = 152.2 %
12V --> 1240 ---> 1240/1100 = 112.7%
13.2 = 100%
14V --> 990 ---> 990/1100 = 90.0%
16V --> 805 ---> 805/1100 = 73.2%
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Old 11-22-2011, 08:46 AM   #7
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sounds correct.

but i would have just done 1240 - 990 / 2
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