Brake duct "optional"?

[tmoretta]

What is the story with the so-called optional front brake duct trim and mesh? Manual says use only if you are going to duct the front brakes. Any empirical info on the effect of these? Are they only beneficial if you fully duct to the backing plates? Do they negatively effect aero?

[JeromeS13]

What is the story with the so-called optional front brake duct trim and mesh? Manual says use only if you are going to duct the front brakes. Any empirical info on the effect of these? Are they only beneficial if you fully duct to the backing plates? Do they negatively effect aero?

IIRC, the best results in the wind tunnel were with those taped off? They're pretty much just for aesthetics, unless you're ducting to the brakes, as stated.

[C.Plavan]

You most likely will never need any brake ducting on the 818. Its too darn light. I did not cut any of those area's. If ever needed, I would just add a scoop from underneath the LCA.

[tmoretta]

I thought it was the small square openings on either side of the grill opening that were taped off to maximize aero.

[Scargo]

I never know whether I'm speaking out of turn or giving out bad info to the 'S" crowd, but I will certainly be using brake cooling ductwork off the front fascia on my R. The openings can be taped off if the brakes are not getting up to temp.
I would find that hard to imagine on a race car, but agree it probably is not needed on a pure street car and other less invasive ways of cooling them is possible without violating the front facia.