This is NOT intended as a "knock" of some of the aftermarket "cool air" induction setups some here are using, only the results of an informal test done on my own truck...
I recently installed a NAPA BHAF on my '02 truck, and in connection with another temperature related project, decided to also see as nearly as possible what the underhood temps were in the area around my BHAF as compared to ambient outside temperatures - here's my BHAF setup:
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SOOOooo, with outside temps at an indicated 91 degrees, and after a 5 mile drive on reasonably level road at 55 MPH or so, my underhood temp over on the inside of the BHAF, next to the turbo, registered just under 100 degrees - an increase over ambient of about 10 degrees.
Now, I gotta wonder exactly WHAT real-world benefit is to be obtained by hacking holes in firewalls and installing fancy ductwork - all to (hopefully!) reduce intake air by another 10 degrees...
Nor is mine the first such test I have read about - and the others also indicate about a 10 degree underhood rise in temperature at common freeway speeds...
Just a FYI to ponder...

I recently installed a NAPA BHAF on my '02 truck, and in connection with another temperature related project, decided to also see as nearly as possible what the underhood temps were in the area around my BHAF as compared to ambient outside temperatures - here's my BHAF setup:
SOOOooo, with outside temps at an indicated 91 degrees, and after a 5 mile drive on reasonably level road at 55 MPH or so, my underhood temp over on the inside of the BHAF, next to the turbo, registered just under 100 degrees - an increase over ambient of about 10 degrees.
Now, I gotta wonder exactly WHAT real-world benefit is to be obtained by hacking holes in firewalls and installing fancy ductwork - all to (hopefully!) reduce intake air by another 10 degrees...
Nor is mine the first such test I have read about - and the others also indicate about a 10 degree underhood rise in temperature at common freeway speeds...
Just a FYI to ponder...


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