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Old 7th July 2008, 07:06 PM   #39 (permalink)
tarmac-
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Re: Science behind 'Colder air = More Power'

Quote:
Originally Posted by Coupe-R View Post
UHHHH in a honda thats like one of the biggest factors affecting fuel apart from the raw fuel maps it self.

IAT=Intake Air Temperature sensor
There is a table in the ecu for IAT vs fuel (OBD0 has this also in BRE)

it matters a shit load to tune this correctly, especially with big injectors, if you have this wrong. Winter comes around and boom goes your car, not enough fuel added at that temp. (depends how you set up the base map tho)

This is also the reason why people running big injectors with VAFC2 have a dam rich cold start, they can't change offsets for cold coolant temps, and cold air temps, cold starts etc which=more fuel delivered

You've been living in nissan world too long
The airflow sensor has the temp conversion in the sensor already, and then the zone the ecu reads on a nissan ECU is determined by "TP" theoretical pulse width) This is measured from the air flow voltage, the Crank angle sensor, RPM, cylinders ect into a forumla the ECU calculates all the time so it knows which zone to read off at the specified RPM.

nissans have a complicated system because they are air flow, but do not require a IAT vs fuel talbe as such, because the air flow metre compensates for this.


Yeah, was joking hence the :p
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