Cant' find where "heat soak" was discussed on the forum so putting it here.
I typed in the phrase "heat soak" and "Ford" can found this product. It says it fits a Navigator and the Ford GT engine is Navigator based (though alloy block) but I don't know if there's room for it. Anyway maybe somebody can investigate if heat soak is barring the engine from more performance. I found the product description on the site www.foximas.com
"GMS Performance Mass Airflow Sensors
PERFORMANCE MASS AIRFLOW SENSOR 10 to 15 horsepower increase at rear wheels! 50-state legal Innovative sensor features a state-of-the-art active-electronic module that provides improved control of both ignition and injector timing, contributing to the big horsepower gain at the rear wheels. 47% more airflow capacity than stock sensors. Sensor is housed in a high-impact injection-molded body to reduce heat "soak", a problem common to stock metal sensor. Installation of this sensor will not affect mileage or drivability under normal conditions. Easy to install in minutes. Instructions included. Applications:1999-2003 Ford F-Series Pickup F150; F250 w/4.6L; 5.4L (exc. Supercharged),1999-2003 Ford Expedition with 4.6L; 5.4L (exc. Supercharged),1999-2003 Ford F-Series Pickup F150; F250 w/4.6L; 5.4L (exc. Supercharged),1999-2003 Ford Expedition with 4.6L; 5.4L (exc. Supercharged)
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I typed in the phrase "heat soak" and "Ford" can found this product. It says it fits a Navigator and the Ford GT engine is Navigator based (though alloy block) but I don't know if there's room for it. Anyway maybe somebody can investigate if heat soak is barring the engine from more performance. I found the product description on the site www.foximas.com
"GMS Performance Mass Airflow Sensors
PERFORMANCE MASS AIRFLOW SENSOR 10 to 15 horsepower increase at rear wheels! 50-state legal Innovative sensor features a state-of-the-art active-electronic module that provides improved control of both ignition and injector timing, contributing to the big horsepower gain at the rear wheels. 47% more airflow capacity than stock sensors. Sensor is housed in a high-impact injection-molded body to reduce heat "soak", a problem common to stock metal sensor. Installation of this sensor will not affect mileage or drivability under normal conditions. Easy to install in minutes. Instructions included. Applications:1999-2003 Ford F-Series Pickup F150; F250 w/4.6L; 5.4L (exc. Supercharged),1999-2003 Ford Expedition with 4.6L; 5.4L (exc. Supercharged),1999-2003 Ford F-Series Pickup F150; F250 w/4.6L; 5.4L (exc. Supercharged),1999-2003 Ford Expedition with 4.6L; 5.4L (exc. Supercharged)
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