Limit of MAF reported.
03-30-2004, 08:39 AM
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Limit of MAF reported. Just got the car out of storage yesterday, after doing some porting on the Throttle Body and blower and cleaned out the rough casting in the Intake manifold,
Before this work the autotap log reported a maximum 424.38 gm/s - IAT 40deg.
Now (after) again the maximum is 424.38 gm/s - IAT 100deg.
The MAF is still stock with the screen and I thought maximum should go to
428.46 the last value in the table.
The car is running very strong like I remembered, Is 424.38 a limit or just coincedence?
Before this work the autotap log reported a maximum 424.38 gm/s - IAT 40deg.
Now (after) again the maximum is 424.38 gm/s - IAT 100deg.
The MAF is still stock with the screen and I thought maximum should go to
428.46 the last value in the table.
The car is running very strong like I remembered, Is 424.38 a limit or just coincedence?
03-30-2004, 10:01 AM
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Your MAF table on a car that came with a plastic Delphi
85mm MAF should run to 12000Hz. My MAF tables show
this to be 428.46 for an '01 Z06, but I believe '02 may
be different slightly and I don't have that table. If the
MAF Frequency is under 12000Hz then the value will be
interpolated. If it's over, the value will limit (I believe) at
the last table entry. Table entries can change from model
to model and year to year. Can you see the raw frequency?
Can you see the actual MAF table entries (LS1-Edit, HPTuners
etc.)?
511 gm/sec is supposed to be the PCM's internal limit. F-Body
MAF tables limit at 11250Hz, 439 gm/sec but the 85mm Delphi
MAF vehicles limit at 12000Hz, and anywhere from 428 to 453
gm/sec (would love to know whether this is anything intrinsic
to the MAF body, or just GM modeling other intake tract
effects).
85mm MAF should run to 12000Hz. My MAF tables show
this to be 428.46 for an '01 Z06, but I believe '02 may
be different slightly and I don't have that table. If the
MAF Frequency is under 12000Hz then the value will be
interpolated. If it's over, the value will limit (I believe) at
the last table entry. Table entries can change from model
to model and year to year. Can you see the raw frequency?
Can you see the actual MAF table entries (LS1-Edit, HPTuners
etc.)?
511 gm/sec is supposed to be the PCM's internal limit. F-Body
MAF tables limit at 11250Hz, 439 gm/sec but the 85mm Delphi
MAF vehicles limit at 12000Hz, and anywhere from 428 to 453
gm/sec (would love to know whether this is anything intrinsic
to the MAF body, or just GM modeling other intake tract
effects).
