Intake Air Tempeture IAT How does it affect timming?

a_sesshoumaru

Suprita
Jan 7, 2007
455
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El Salvador
i have a map ecu 1, it only controls fueling but i can not control ignition timming, and i have noticed as long as you scale down the maf frecuency due to bigger injectors the agresivier gets the timming. I know the stock ecu has its ways to save the motor from knocking retarding ignition timming and i think one way could be making the IAT reading high tempetures. Could it work? is there any way someone can monitor the ignition on low and high tempetures? i could sound crazy but i have my iat tapped to a hole where the hooks to pull down the engine are in the cylinder head to make it read a really high tempeture, i hope someone can clarify this. To run 20psi safe i guess i need to run like10degrees less.
 

Supracentral

Active Member
Mar 30, 2005
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If you plug a resistor into E2 & THA you "hardwire" the temp. E2 & THA are where the factory temp sensor was connected in the original AFM.

When I used to tune cars professionally, this is one the tricks we used to get better/safer tunes on the cars than the amateurs did.

2400 ohms is what is normally used and should simulate about 70 deg F. 1200 ohm would fake it out to about 106 deg F. I'd start there and see how much retard that give you. Then step down at 100 ohm increments. Resistors should cost a couple of pennies a piece, so get a bunch and experiment until you get the timing map you want.
 

a_sesshoumaru

Suprita
Jan 7, 2007
455
0
0
El Salvador
Supracentral;1685739 said:
If you plug a resistor into E2 & THA you "hardwire" the temp. E2 & THA are where the factory temp sensor was connected in the original AFM.

2400 ohms is what is normally used and should simulate about 70 deg F. 1200 ohm would fake it out to about 106 deg F.
Thanks
 
Last edited:

Supracentral

Active Member
Mar 30, 2005
10,542
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36
a_sesshoumaru;1685741 said:
will this retard my ignition timming?

It's used for both fuel and spark calculations, so it's not easy to trick one without messing with the other.

With some trial an error you should be able to find a happy medium.

If you want real control, move to a standalone.