Only the splitter, no rubber dam (I was referring to the whole darn thing as the air dam). It is 'attached' so I can't experiment with that, but compared to stock it must be creating some extra resistance.
QUOTE(r_towle @ Apr 3 2024, 05:22 PM) 
I’m recalling a set of tests to measure air going into the engine lid, along with temps with and without the rain tray…lots of good tests.
Tray or not makes no difference.
I found this to be the case also. August in North Carolina, generally in the mid 90's with 80-90% humidity. I removed the rain tray and ran two weeks without it just to see if there was any difference. Head and oil temps were exactly the same. Operating temp is operating temp, and has more to do with state of tune as well as whether all the cooling tins are in place.
Over the course of an entire year, through winter and summer, I also saw ambient temps make no difference in head temps, however oil temps were slightly higher in the summer (although not enough to be concerned about) even with a remote oil cooler with thermostatically activated fans.
It’s not the resistance that is a problem from a low air dam
It’s the cooling
Under air is required to help evacuate the hot air and increase the temperature fficiency of the stock cooling design
10 degrees was my result also from my own experience with air dams
It’s the cooling
Under air is required to help evacuate the hot air and increase the temperature fficiency of the stock cooling design
10 degrees was my result also from my own experience with air dams
Ahh, yes, I see. I suppose that big oil cooler slot lets some through.... nothing like a regular front of course.
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