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98 maf limit - is it the maf sensor, or the pcm?

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Old Oct 19, 2005 | 02:31 PM
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Default 98 maf limit - is it the maf sensor, or the pcm?

Because if it's the pcm, I can rescale the maf output signal before it gets to the pcm, by 10-15%. A 15% rescale will handle about 50% more airflow.

That is if the maf sensor will continue to output a higher frequency and not freeze at some ceiling.

What is the upper limit the maf sensor will generate?

And since I have a Granatelli 85mm maf sensor (with resistor removed), will it have a higher output limit than the stock '98 maf sensor? And does anybody know what that upper limit is?
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Old Oct 19, 2005 | 03:26 PM
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11250 is the frequency limit, and 512 grams a second is the pcm internal limit.

You can scale all of the airflow tables to get around this though

Ryan
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Old Oct 20, 2005 | 12:14 PM
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Originally Posted by slow
11250 is the frequency limit, and 512 grams a second is the pcm internal limit.

You can scale all of the airflow tables to get around this though

Ryan

Like how? I'm not following you.

I'm thinking the table in the pcm only goes out to a certain frequency too.
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Old Oct 20, 2005 | 03:06 PM
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I thought you couldn't use a non-resistor-modified MAF, such as a Delphi 85mm, since the celing on the PCM...

The table only does go out to a certain frequency and the MAF's are capable of outputting a higher frequency than our PCM's can handle. That was always my conception before anyhow.

I just so happen to have a Delphi 85 laying around (it's actually installed right now but I'm running SD for the time being)...so does this mean I can adjust some tables and actually use it without hitting the celing?
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Old Oct 21, 2005 | 03:11 PM
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ttt since I would like to know more about this (my question and the one from rush7)
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