91 vette.. what should the map sensor read.

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Nov 24, 2004 | 11:48 AM

mos90

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Drifting

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From: rome ny

91 vette.. what should the map sensor read.

im just making sure everything is working properly, what range should the map sensor voltage be ?

Nov 24, 2004 | 11:55 AM

conv90

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From: Milan

Quote:

Originally Posted by mos90

im just making sure everything is working properly, what range should the map sensor voltage be ?

Voltage?
My KPa readings are with stock cam (not you case)
idle in park or nutral: about 34 or 35 Kpa at 775rpm
idle in D with brake pedal on: about 43 or 44 Kpa at 675 rpm
At KOEO: 99,9 kpa
at WOT : up to 99,8 kpa

HTH
-Beppe-

Nov 24, 2004 | 01:06 PM

mos90

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Drifting

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From: rome ny

my scanner shows the map sensor voltage, not kpa. not sure how to convert..

Nov 24, 2004 | 01:09 PM

kittmaster

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From: RI

The voltage should swing between 5V to .5V between full throttle to idle

(shooting from memory)

Chris

Nov 24, 2004 | 06:01 PM

Mo_Bandy

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From: Fremont Oh

If you are supercharged the stock map will read up to 104 KPA but he above KPA and voltages are correct...

Mo

Nov 24, 2004 | 06:06 PM

bobmic93

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From: Chicago Illinois

Quote:

Originally Posted by Mo_Bandy

If you are supercharged the stock map will read up to 104 KPA but he above KPA and voltages are correct...

Mo

Never heard of kpa . What does it mean?

Nov 25, 2004 | 01:28 AM

Mo_Bandy

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From: Fremont Oh

KPA is Kilopascals it is metric for pressure readings 100 Kilpascals =14.7 psi or atmosheric pressure

21" Hg = ~30 Kpa

18" Hg = ~40Kpa idle

15.5 " Hg = ~50 Kpa

10 " Hg = ~70 Kpa part acceleration

7" Hg = ~80 Kpa harder acceleration

4" Hg = ~90 Kpa vitrually wide open throttle

0" Hg = 100 Kpa WOT

" Hg is inches of mercury
Hope this helps...

Mo

Nov 25, 2004 | 02:54 AM

conv90

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From: Milan

Since you have a 91 (mine is a 90) you have an $8D code.
The $8D code outputs the MAP sensor ADC counts. This can be converted to a voltage by:

VOLTS = ADC * (5/255)

To convert from ADC counts to KPa I use:

KPa = ADC * 0.369 + 10.415

-or-

(KPa = ADC * 0,369 + 10,415)

-Beppe-