what all affects Kpa in a tune??

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Jul 17, 2007 | 07:41 PM

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From: Butler, PA

what all affects Kpa in a tune??

I hope this is a ok question. I dont know that much about tuning but I wanted to know what can affect Kpa?

thanks

Jul 17, 2007 | 07:43 PM

foff667

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From: Clermont, FL

not much in tuning affects your map reading. Its usually mechanical parts ie camshaft, intake, vacuum leaks that affect your map readings.

Jul 17, 2007 | 08:56 PM

wait4me

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From: warsaw, in

KPA is just a measurement from the map sensor that the pcm uses to determine several things in the tune. If you are getting odd readings, As Foff667 says, it could be from bad sensor, vacuum leak, pinched/damaged wiring, Not plugged in, ect..

Jul 17, 2007 | 09:09 PM

SSpdDmon

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From: Commerce Twp, MI

As stated, for the most part it's the mechanicals of the motor that play a role in kPa (or absolute manifold pressure, which is atmospheric minus manifold vacuum). HOWEVER, you can see changes in kPa at idle by changing the desired idle speeds, base spark, and fueling. As absolute manifold pressure (kPa) increases at idle, idle quality decreases...

Jul 17, 2007 | 09:44 PM

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From: Butler, PA

could a bad map sensor cause the Kpa to read normal from idle to 5000 rpm then drop down after 5000 rpm's?

Jul 17, 2007 | 09:47 PM

wait4me

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From: warsaw, in

No, i would say a massive intake restriction.

Jul 17, 2007 | 10:16 PM

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From: Butler, PA

Quote:

Originally Posted by wait4me

No, i would say a massive intake restriction.

As of now Im running a Volant twin cone cold air intake, into a descreened 85mm MAF into a 90mm TB and 90mm FAST. I think the induction setup is pretty good.