Ducting is always a last resort. It introduces thermal stress from the temperature swings that you ideally want to avoid.


Real world example: Porsche RS-R GT-LM cover up the brake duct as much as possible and use the absolute bare minimum. Look at photos from different track to see different levels of open-ness on the duct. Sebring? Big opening. Long Beach? Medium opening. Watkins? Small opening.

I'm running front rear (without ABS), like 'em a lot...
This is after being disappointed with XP10, Winmax W5, PMu CR, etc.
Great but not too grabby bite, consistent performance over wide temperatures, not too too loud, dust is not bad, they're fairly durable, and pretty streetable as well.

How long should pads be lasting me? I have been eyeing those for a while.

Life varies by driver, car prep, track, conditions, etc., but typically if you're needing to replace pads every 5 track days or less, you can probably use an upgrade.

You can also look at it as 8 hours of track time or less, you can probably use an upgrade.


With brakes, too much is often safe, but not enough results in both dangerous situations as well as having expensive paperweights.

interesting, hadn't considered the thermal stress angle.

has anyone done testing to putting the ducting behind the radiator, which would pre-warm some of the air but still maintain a positive air flow?

Let's say your radiator has 100% efficiency (it doesn't), and warms the air to 180F. That's still a huge difference from a 800F rotor.

50F, 100F, or 180F, is still all a huge difference to a 800F rotor.

You're better off using a smaller amount of air (it'll all mix anyways), rather than "warmer" air.

As a drop of extra info. I removed my ducts when I went to a BBK setup. My discs were cracking by the time I got to replace my pads on OEM size, I didnt want to risk the more expensive 2 piece rotors crack as fast, considering pads would last much more than before. So far, I change rotors with pads as a precaution, but they could still go on. (lastting about 2-3 times as much as before the BBK).

Damn, this is surprising. I just put on new XP8's F&R with new blank rotors for the street and the stopping power is almost as comparable to my 2016 Mustang GTPP with 6 piston brembos and 15" rotors, but they don't bite anywhere near as hard. Still, I've put them through their paces on the street, but I plan to track the car next year and was hoping they would hold up. I guess we'll see.

So after going with PMU Club racers on the front I’m sold on their ability to not fade. I was really pushing them hard all day long for a 2 day in the 90’s by the second day and they kept asking for more.

The longevity is a bit in question because I’m not sure they’re going to last long. This is after just a 2 day.

You've already faded them, just not catastrophically.

You MIGHT get 3 more days out of them, but likely will be having issues on the 4th an 5th day.

What tires are you running? Any suspension mods? N/A engine?

245/40/17 Falken 660's
Fortune 500
Just headers and a tune as far as engine goes

PMU pads seem to crumble like that. There is a localish guy to me with a stock performance package car with SX2's. He had the same issue with the Club Racer pads.

How do you like the Fortune 500's. I've been eyeballing the 510 as an upgrade from stock.