Water cooled brakes

I’m not sure it’s the same. The mist is well away from the wheels and would never be a stream. Aimed at the brakes, I’d be surprised if any liquid even touched concrete. Beyond that, a system failure would be unlikely to dump much water because the reservoir would be up and before a pump.

I hear the concern, but I think this is different in enough ways to matter.  I think an intentional intermittent mist and and accidental dump of a reservoir are materially different, not least of which is that your example is an edge case. If the dumped reservoir issue was common enough to be a concern, there’d be more rules about how to secure the reservoirs for cool suits.

It's a problem under Rule 3.8.7. "If any staff member sees a suspect leak, you will be immediately black-flagged..." The key word there is "suspect." Any leaking fluid will get you flagged, as the flaggers have to assume the worst, so it's a fuel leak until proven otherwise. If they see the leak again, you get flagged again. Nobody is going to say "Oh, now that we know that car is deliberately spraying water from its underside, we'll go ahead and assume the leak isn't fuel this time."

Water has a pretty good heat capacity and heat of vaporization but my guess (based on my Ph.D. in thermal transport, yes, really) is that a washer-nozzle mist during braking isn't going to gain you anything noticeable in terms of cooling. If you try to direct more water than that at the brakes, you're quickly back to the problem of getting flagged and/or needlessly contaminating the track surface right in the braking zones, which is to say precisely the locations where you are least likely to make friends by doing so.

I hope not.

Lemons strives to avoid a lengthy set of rules, as it's impossible to cover everything anyway. There are a lot of things not explicitly named item-for-item in the rules that still won't be allowed on track. I doubt this proposed spraying system would be allowed.

IMO brake 'upgrade' solutions don't usually generate the desired outcome.  Think about these two questions:

1. What really stops your car?  Hint: It's not the brakes.

2. Can your current brake setup lock the wheels, at will, every lap, for the entire race, without fade?  If your answer is "yes" your brakes are currently doing all they can do as limited by the correct answer to question #1.

FWIW, we have ZERO ducting on our FWD car.  We have never had brake fade or the inability to lock the wheels on our non-ABS setup.  The ST-43 pads we run usually last at LEAST three entire races, maybe longer depending on the track.   

As always YMMV.

Remove the wheels and tires from your car and let me know how fast your car stops using the brakes.

Tires stop the car.  Hence better sticky tires, stop quicker than all-season bricks.

I tried that once between turns 8b and 9 at The Ridge and the car stopped just fine. It took a while to get it going again afterwards, though, so I don't recommend this approach.

I support the amount of overthinking going on in this thread, well done.

Don't water cool your brakes. For one, you risk cracking the rotors if it doesn't work as designed. (you do not want to shock an over heated rotor). For another, you run the risk of black flags and then having to explain to the judges that you're spraying water at your brakes. Neither of those reasons even consider anything performance oriented but are enough to shut down the idea.

Use good brake pads, and even more importantly use good racing fluid. You can absolutely boil cheap street fluid, and boiled fluid is horrifying. It doesn't come on gradually like pad fade, you go from functional brakes to a pedal on the firewall in-between presses. Add brake ducts if it makes you feel better.

Murphy's law is a bitch... I understand it's not the same mechanism, but the potential result is the same. What happens when your hose or mist nozzle breaks on one of the two sprayers and your driver kicks on the pump motor? My point is that you're intentionally putting your team and other teams in danger by doing this. The point I was trying to make is once Murphy's law kicks in on your "engineered" brake cooling apparatus the vehicle is going to shoot you harder than losing a wheel (I've shot off a wheel mid-corner, a wet single corner under throttle was way worse).

Also, there is a rule for securing cool suit reservoirs... the ratchet strap required per rules somehow broke. Now we have 3 redundant methods holding down our ice chest. Again, Murphy's law... especially with anything that is or could be safety related.

3.6.8     Cockpit De-Scuzzification.  Large items like cool-suit chests must be extremely well secured by purpose-built metal retainers or at least two very well secured, heavy-duty, fully ratcheting tie-down straps.

Thanks! 

Ours is secure (bolted to the floor), but I didn't recall seeing it actually written in the rule book.

By the way.....
Three pedal mafia's Toyota Cressida was leading the race when a water drip from their cool-suit cooler got them Black flagged!

Manny