To vent front brakes or not?

[KSPropbender]

I am thinking about running a fog light valance in the S10 im building and then ducting the air back onto the front rotors, but I am concerned with how to then get that air back out from under the truck. I can't run a belly pan or rear diffuser, and my splitter cannot extend behind the axle centerline if I want to stay within the class specs that I am building this truck to. How are you guys addressing this issue? I would rather run unvented brakes than pack air under the truck causing lift.

[NOT A TA]

If you run brake ducts to the front rotors the air will escape out the wheel well opening and shouldn't increase lift.

[dutch55]

NOt A TA is correct, there are plenty of places for the air to escape from the wheel wells, and also through the openings in the wheels. Besides, the cross-section of a brake duct tube isn't going to be enough to increase the underside pressure to the point you would notice lift.
You can aim the air at the inside rotor face, or even better, build a duct so the air is directed at the inner hub area of the rotor so the cool air is pumped from the center out by the vent slots in the rotor.

But are you really going to run open track events with enough consecutive laps that you need to worry about the temps?

[KSPropbender]

But are you really going to run open track events with enough consecutive laps that you need to worry about the temps?
Highly doubtful, just covering bases while I'm building it.

[NOT A TA]

Highly doubtful, just covering bases while I'm building it.

Then save the weight, hassle, and expense and don't bother with ducts unless you start doing track days.