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Old 01-05-2008, 03:10 AM   #1
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Default MAF IAT Values

Anyone ever bother to map out the values from the IAT in a 94-97 MAF? I know most people just use the GM sensor but I'm not ready to use that until I'm rocking some boost.. Kinda wanna get a good feel for everything with MAF and all in place before I start ripping more than emissions off.
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Old 01-06-2008, 02:14 AM   #2
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DIYAutoTune would know for their MSPNP, but you would have to work out the bias resistor in the factory ECU yourself.
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Old 01-06-2008, 07:54 AM   #3
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Uh guys the mspnp is designed to run with the stock maf just use there easytherm values.
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Old 01-06-2008, 10:10 AM   #4
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I'm pretty sure the rx7 defaults will work.

*C

20 41500
50 11850
85 3500

bias is 47000, so if you have R4 installed, make it 49490
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Old 01-06-2008, 05:11 PM   #5
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I have the 2.49k ohm installed in R4, so I should still select 49490?

When I wrote my easytherm for stock CLT (RX7 settings) I thought I selected the RX7 default for IAT too, but it didn't really seem correct to me when I was playing with it on the car. Maybe I used the wrong bias value in Easytherm?
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Old 01-06-2008, 08:58 PM   #6
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yeah, you gotta add 2490 to the bias of each.
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Old 01-07-2008, 12:14 AM   #7
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Son of a bitch.. So the Bias setting in Easytherm for CLT should be 4980 since I'm using the 2490 ohm on the board?

Dunno why I'm not understanding this..
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Old 01-07-2008, 12:21 AM   #8
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basically you're telling it what resistance is on the line. r7 and r4 are both 2490 reistors. if you're sharing the CLT and AITsignal, you gotta add 2490 to the OEM ECU values.

if you arent using the stock ecu, then the bias will only be 2490.

easiest way to determine is just measuring the resistance at the sensor connector with the MS in place.
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Old 01-07-2008, 12:24 AM   #9
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He is saying if you have the bias resistor installed on the board and you are in parallel with the stock ecu you have to add 2490 to make the bias 4980. So the answer is yes.

This might not work. I'm working with Paul to help him figure out why his CLT sensor won't read accurately this way

Edit: Too slow again.
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Old 01-07-2008, 02:15 AM   #10
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Ooooooooh.. That makes sense!

No, I'm full standalone so I just use 2490 in both easytherm values. Thats whats been confusing me.
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Old 01-07-2008, 02:22 AM   #11
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Quote:
Originally Posted by elesjuan View Post
Ooooooooh.. That makes sense!

No, I'm full standalone so I just use 2490 in both easytherm values. Thats whats been confusing me.
correct.
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Old 01-07-2008, 10:13 AM   #12
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i forgot you have a 95.

you should use:

degF

-4 16150
104 1150
176 320
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Old 01-26-2008, 05:03 PM   #13
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Bringing back an old thread because I'm still trying to get things correct here.

Running stand alone v2.2 on a 1995 with MAF for IAT. Have the Default resistor installed.

Entered 2490 ohms in the bias of the IAT box, entered degF

-4 16150
104 1150
176 320

CLT is about 50 degrees which is ambient air temp. The IAT shows 72 degrees. Did I do something wrong?
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