q: parallel MBC -- boost lag & tuning strategy
03-28-2005, 01:43 PM
#33
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It's been pretty consistent, either way.....
Here is some from when it was warmed up:
RPM MAF
800 4.78
800 4.25
760 4.17
760 4.22
760 4.5
760 4.5
760 4.47
760 4.33
760 4.33
760 4.44
760 4.5
760 4.5
800 4.5
800 4.69
760 4.72
800 4.69
Here is some from when it was cold:
RPM MAF
760 4.69
800 4.61
760 4.53
800 4.53
760 4.5
800 4.56
800 4.47
800 4.42
760 4.42
760 4.42
760 4.42
760 4.44
760 4.47
800 4.42
760 4.42
760 4.42
760 4.47
760 4.42
760 4.42
760 4.44
760 4.42
800 4.5
800 4.5
760 4.61
760 4.5
These are all combined from different days/temps so you can see that it is pretty consistent, ~4.5 g/s.
RPM MAF
800 4.78
800 4.25
760 4.17
760 4.22
760 4.5
760 4.5
760 4.47
760 4.33
760 4.33
760 4.44
760 4.5
760 4.5
800 4.5
800 4.69
760 4.72
800 4.69
Here is some from when it was cold:
RPM MAF
760 4.69
800 4.61
760 4.53
800 4.53
760 4.5
800 4.56
800 4.47
800 4.42
760 4.42
760 4.42
760 4.42
760 4.44
760 4.47
800 4.42
760 4.42
760 4.42
760 4.47
760 4.42
760 4.42
760 4.44
760 4.42
800 4.5
800 4.5
760 4.61
760 4.5
These are all combined from different days/temps so you can see that it is pretty consistent, ~4.5 g/s.
03-28-2005, 05:07 PM
#35
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here's the MAF graph & data ...
<b>idle:</b> (warm)
<img src="http://bagodoosh.home.comcast.net/s4/002_mbci.gif">
<b>raw data</b>
(temp about 38F)
RPM Engineload FI time MAF
760 20.3 2.38 4.64
760 20.3 2.38 4.61
760 20.3 2.38 4.58
760 20.3 2.38 4.58
760 23.3 3.06 7.17
760 24.8 2.72 5.36
720 24.1 2.72 5.47
760 24.8 2.72 5.64
720 24.8 2.72 5.69
760 24.8 2.72 5.56
760 24.8 2.72 5.61
760 24.8 2.72 5.61
760 24.8 2.72 5.61
760 24.8 3.06 5.61
760 24.8 3.06 5.61
720 24.8 2.72 5.61
720 24.8 3.06 5.61
720 24.8 2.72 5.61
720 27.8 3.4 6.19
760 26.3 3.06 5.83
760 27.1 3.06 6.19
760 27.1 3.06 6.17
760 27.1 3.06 5.94
760 26.3 3.06 6.03
720 27.1 3.06 5.97
720 27.1 3.06 6.03
720 28.6 3.4 6.5
720 29.3 3.4 6.42
760 28.6 3.4 6.42
it's dying, ey?
<img src="http://bagodoosh.home.comcast.net/s4/002_mbci.gif">
<b>raw data</b>
(temp about 38F)
RPM Engineload FI time MAF
760 20.3 2.38 4.64
760 20.3 2.38 4.61
760 20.3 2.38 4.58
760 20.3 2.38 4.58
760 23.3 3.06 7.17
760 24.8 2.72 5.36
720 24.1 2.72 5.47
760 24.8 2.72 5.64
720 24.8 2.72 5.69
760 24.8 2.72 5.56
760 24.8 2.72 5.61
760 24.8 2.72 5.61
760 24.8 2.72 5.61
760 24.8 3.06 5.61
760 24.8 3.06 5.61
720 24.8 2.72 5.61
720 24.8 3.06 5.61
720 24.8 2.72 5.61
720 27.8 3.4 6.19
760 26.3 3.06 5.83
760 27.1 3.06 6.19
760 27.1 3.06 6.17
760 27.1 3.06 5.94
760 26.3 3.06 6.03
720 27.1 3.06 5.97
720 27.1 3.06 6.03
720 28.6 3.4 6.5
720 29.3 3.4 6.42
760 28.6 3.4 6.42
it's dying, ey?
03-28-2005, 07:01 PM
#37
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alrite doc, i'll look into that.
i'm thinking since it happened after my install, a leak on the intake side is less probable.
i'll clamp the hoses to the MBC to rule it out. then i'd have to think about pressure testing.
i'll clamp the hoses to the MBC to rule it out. then i'd have to think about pressure testing.
03-28-2005, 07:42 PM
#39
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I don't think a leaking MBC would cause the ECU to alter the N75 duty cycle profile, --->
---> but the effect of the leak would be premature partial opening of the wastegates. That, in turn, would retard boost rise.