1. I run the stock brakes up front with high pressure air ducted into the "hat" of the vented rotors. The body of my calipers is getting to at least 300 degrees F and the piston is definitely higher. I run Castrol Racing SRF brake fluid and have never experienced brake fade from boiling.
But, shortly into any race (1-2 hours) the heat burns up the dust shields on the caliper piston. Which would be no problem, except that those dust shields prevent the caliper piston from turning. So then the caliper piston will revolve slightly due to the pads slight movement in the caliper body. When they turn the cutout area that is designed to be at exactly 20 degrees to the caliper turns and now the pad will be worn rather severely on a taper because of this. So I need a crazy high temp dust shield or a way to prevent the caliper piston from revolving.
Two things, If you are running vent hoses that depend on just incoming air from the car`s speed you should wire in a couple of bilge blowers to really move air on to the brake center.
The solution to both stabilising the piston and reducing heat transfer from the pads to the dust shield is a couple of thin stainless sheet metal plates cut to the same shape as the brake pads including the retaining holes.
The outer one dhould have a machined relief so that the contact pad on the piston fits through that plate so that it is held in the correct position but the stainless plate must leave the pistons contact area proud of that plates surface.
A second thin stainless brake pad plate should not have a cutout but simply act as an insulator.
You are an E
so you know het transfer is reduced between surfaces and stainless is a good choice for reducing heat transfer.
These should be on both sides of the caliper of course.
The reduction in heat transfer to the calipers is substantial.
2. Front wheel bearings: The car can pull over 1g of cornering force for extended periods and does. A typical race weekend including practice is 20 hours of track time. The front rotors will get blue from the heat all the way around, stopping at the wheel studs. So there is a good heat load. After every race the front hubs come off everything is inspected and repacked with red line synthetic grease. I have tried more bearing preload and less bearing preload. After each race I generally will need to replace one of the inner bearings because it has some very fine beginnings of some marking on the cup portion.
But every 3rd race or so I will find one of the inner bearings cups loose in the hub. Since the bearing cup or race is way harder than the hub, What is happening is that the cup displaces the metal of the hub then can rotate. This is supposed to be a press fit. So game over for that hub.
These inner bearing cups are loctited in with Loctite 620 and are good when installed.
I realize that I am subjecting these bearings to loads beyond what their designers ever intended. But I can make the bearing live but the housing (hub) is the weak point.
The hub material is pretty thin at both front and rear bearing area.
Solution is to reduce expansion due to load on the hub.
I assume you have removed the clip on anti-lock senders from the hub.
But note the area that they took obstructed air flow to the rotor.
I suggest you lightly machine (using a lathe) the outer surface where the inner bearing race and seal fits, to a consistant diameter (it is a casting).
Then take either a section of thick wall STEEL
(not cast iron) tubing or machine a section of round steel plate to a inside diameter a couple of thousandths ID diameter smaller than the finished hub diameter. The OD should be about 1 inch larger than the ID (1/2 inch wall) which will act as both heat sink and prevent growth.
Heat the ring and chill the hub and press it on.