Next attempt to fix screwed up brake bias, and rear brakes overheating. Proportioning valve improved the problem slightly. Perhaps highest friction coefficient at front end may fix the Protlum questionable design.
Theory & idea
Front large rotors + small rear rotors + most likely higher friction coefficient at front brake pads. Common solution offered by manufacturers. Unless, one wants to replace a half of car, you have to work with what you got.
![](https://hajes-racing.com/wp-content/uploads/2017/10/PAGID_Racing-RST_Series_friction_vs_temp-640x295.png)
Ferodo DS2500 are decent brake pads for traffic-light racing, but they fade too quickly. The friction coefficient 0.42 up to 350 °C, dropping down to 0.33 @ 650 °C
![](https://hajes-racing.com/wp-content/uploads/2017/10/Ferodo_Racing-DS2500H_friction_coefficient-640x470.png)
(2022-10-31 UPDATE) Ferodo updated DS2500 (H) friction coefficient vs temperature table. DS2500 used to have 0.41 up to 550 °C – based on comparison with Pagid RST3 I highly doubt so.
Pagid RSL19 optimal temperature range 350 – 500° with friction coefficient 0.42, down to 0.4 @ 700 °C.
Pagid RST3 optimal temperature range 400 – 500 °C (my usual alpine grilling temperature) with great friction coefficient 0.42 from 300 to 650 °C. Peak friction coefficient 0.47 where you need it most 400 – 500 °C.
Mismatch of friction coefficient, and poorly designed suspension is a bad combination.
Thoughts/review
Pagid RST3 are pure race pads that work as promised. You don’t even need to brake hard, they simply brake with a gentle touch of brake pedal.
I never ever used full brake pressure because those high-friction-coefficient pads are designed for racing tires with high grip. My favourite Yoko Advan were still not enough.
Of course, it led to expensive disappointment because it didn’t resolve brake balance issues. It would need wider tires to use heavy-nose-dive braking style, and shift brake balance to front again.
While it braked better than ever, brake bias was still at the rear end. It would need a complete rebuild to fix this shit. Softer/longer springs at rear end, larger brake rotors at front end, and wider tires.
I was never crazy enough to waste my resources – 3’000 € upgrade on 6’000 € family wreck is not a great business idea in my mind. You can put make-up, and dress on a goat, but it will be always just a goat.
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