I am not sure if the Capaldi fascia ducts are a replacement for the factory ducts or they just supply the adapters to the factor ducts.
I had a heating / cooling shop make up the adapters from the factory duct to the hose in aluminum. Cost almost nothing. The guy did it during his lunch break. I did cut up my factory duct though. I think Ford wants like $70 for the factory duct.
Notice there is a hole for a plastic pin that holds the duct in place. Impossible to get to it though with the spoiler on.
With the hose attached and taped up seams
Cut the factory duct short since its a steep angle from the spoiler to just inside center of the wheel well. Want to run the hose next to frame so keeping the duct short helps minimize the angle.
On the hub side I had him make me a bracket that I attached to the bottom two shock bolts. Just have to remove the shock bolts to get the bracket in
He used stainless steel instead of aluminum since he said that the 90 deg bend will stress at the shock and could tear over time. Notice the bolt head at the hub that would keep the bracket from moving towards the rotor.
I see now from what is being discussed that the distance here from the bracket to the rotor is probably not optimal, too far away but that would be easy to remedy by extending the alu tube through the bracket up to the hub and even possibly more oval. Was surprised how malleable alu really is.
It does feed air to the center of the hub though
This was a prototype piece we did in Alu just for fit. Redid the bracket in SS later
Here it is with the hose hooked up
Another thing I learned. Remove the pin that pulls the pop rivet together and put it in by hand and then use a ball peen hammer to crush the other end of the rivet. Make for a almost smooth finish. Impossible to do with the broken off pin in there.
I used 3" hose because of the clearance issues at full lock of the steering. It interferes no matter what you do. I just used a piece of wood and gently squished the hose into an oval where the tire hits the hose. You have max 1 to 1.25 inches from the tire to the frame at full lock. Hose has wire in it and forms nicely. Its street driven and I am just careful at full lock to go very slowly. 3" also fits the factory duct perfectly. Going to 4" you would have to make the adapter more oval.
I might go back and replace the hose with 4" now that it seems to work and rubbing except at full lock isn't really an issue. Might also try the GT350S ducts in the spoiler out front to help duct more air at the inlet up front. Mine is black so it won't look too bad.
Hope this helps someone! Just talk to some heating / cooling place that makes their own ducts. The guy that did mine actually had fun doing it for me knowing what it was for!