Racing Brake is offering a range of 2 piece rotors (S, 3 with big brakes, 3 with standard brakes), admittedly at a premium, with convergent vane design that reportedly increases cooling air flow. Big plus for those with deeper budgets is that the rotors save significant unsprung weight. I suspect that the convergent vane design, on the 3 PUP brakes, will be roughly comparable to the stock S brakes, at a cost premium but with a weight reduction instead of weight gain. Here is a white paper written by numerous PhDs, explaining the
technical details on how various design and structural parameters effect heat dissipation. I doubt anyone would want to read this (I sure didn't) but you can surf to the conclusions on page 109.
The curved convergent vane design of these rotors appears to be the smart way to reduce weight, and get better management of thermal stresses - for a price of course. It's all tradeoffs. While putting on S calipers and rotors might be the best value for increasing braking thermal capacity/per $, the weight difference between S brakes and rotors vs. PUP brakes with these lighter weight rotors might be as much as 20-25 lbs/corner. That's a lot of weight, and its importance is magnified if you are tracking the car, as weight for sure is your main enemy for all aspects. I'm reminded of Colin Chapman's aphorism, "do your best design, and then add lightness!"
I've ordered a set of four, due to arrive in a week. I'll post pictures, and impressions, although at this point, I'm not tracking the car.
