(EBC is very good, but don't go crazy with super hard racing pad material
I would agree with that.
The slots and holes are to help with heat removal.
Braking, creates a lot of heat, just in the nature of how it does things.
I have heard from some racers that groves (slots) and holes are the best thing ever.
From other racers that they want as much friction on iron (or fill in the blank of material used) as they can get (ie: no holes or slots) more air flow through the cooling fins to remove said heat.
I don’t have an answer on slots (groves) or holes – other than that.
I do like to drive cars hard and have been known to drive in the mountains where there are several 15 MPH (hairpin) turns right after each other – and had experienced brake fade (brakes hot enough to boil the brake fluid) only a few times.
I do recommend removing the brake rotor dust shied to help with air flow (if plans on driving hard) – with a
couple of concerns on doing so.
One is do not drive “hot” brakes through a water puddle – or you have a strong likelihood of warping the brake rotors (always good idea for anyone).
The other is one might put some kind of a shield around the outer tie rod boot (towards the rotor), like Chrysler part number 4656672AA, to prevent heat damage to the boot. There is not much too it and a person could make one themselves with some thin steel plate and tin snips.
I have a few at home – but not sure they are hiding at (for a picture).
The brake rotor creates "cooling" air flow using centrifical force. Incoming air has to go between the existing dust shield and the hot brake rotor. By removing the existing dust shield, a lot more air flow can be accessed to cool the brake rotor – and according to one race friend, thereby one doesn’t need holes or slots.
With no testing data – I will leave my friend’s thoughts – as is – but more air flow and more pad to rotor surface area, does sound more logical.
BudW