Can we talk about brake cooling?

[Estoril]

To be fair, I do not know if I need brake cooling yet or not. This is more for information gathering. I have bought the wrong stuff enough times to know that it's best to look into things carefully and ask the forum before jumping in, which is really the purpose of this thread. And maybe it will help some other people too.

My track car runs OE calipers with PFC-11s. Even on 98-100F July track days, I have no fade. My tires will get greasy before the pads. The greater heat issue could be seizing a caliper piston, which I have done once 6 years ago. Now I rebuild calipers every Spring - no problem since.

I've never had fade on my street M3 and can't envision the scenario where I would.

[OldRanger]

Even on 98-100F July track days, I have no fade. My tires will get greasy before the pads.

How about last weekend at Summit...hot!!! I was there, but not driving, my son was...but we are eating through PFC 331s faster than I would like (6-8 track days). He doesn't overwork the brakes, no ABS typically but still under 1:27 pace in that heat on best laps.

Estoril Do you still have the OE backing plates in? Do you have any brake cooling?

[Estoril]

How about last weekend at Summit...hot!!! I was there, but not driving, my son was...but we are eating through PFC 331s faster than I would like (6-8 track days). He doesn't overwork the brakes, no ABS typically but still under 1:27 pace in that heat on best laps.

Estoril Do you still have the OE backing plates in? Do you have any brake cooling?

I was at this weekend's DE on SP Main. As you said - very, very hot. Me: PFC-11 front/rear. Stone guards are removed, dust guards in. No fade late braking in Instructor group. RE71-R were fine with sane starting pressures with a 33-34F hot target. No additional brake cooling mods. I do a true cool-down lap before pitting.

It is possible for me to push this setup to the limit on Shenandoah regardless of ambient temperature with not-great braking technique. Cleaning up braking technique and driving the car there like a momentum car solves that problem. Shenandoah doesn't give brakes much of a rest in cooling if there are a lot of braking events. Over-braking is a popular cause (not saying it is your son's cause).

Mike told me Saturday that the September Shenandoah event is almost full. I recommend you sign-up very soon! It is a great track, as you know. Better yet in Fall.

[L0okitzRaj]

I'm running pretty much a full hard motorsports setup.


And then their ducts that replace the entire fog light, which still looks stock enough that it doesn't bother me:

can you leave the windshield washer reservoir in with those intake ducts?

[Obioban]

can you leave the windshield washer reservoir in with those intake ducts?

I don't actually know. I have the e39 high intensity tank in the drug bin, and don't run the stock tank (in an effort to get weight off the nose of the car).

[D-O]

Bringing this one back again.

I am replacing my front wheel bearings and hubs, and it seems like this would be the time to install a backing plate with provisions for a cooling duct.

I kind of like the way the speed engineering kit uses the existing brake cooling ducts. https://www.speedengineering.de/en/p...-complete-set/

Anyone have first hand experience with this kit? Any big advantages the Hard Motorsport kit has over the Speed Engineering kit?

D-O

[trevorae46]

Which I like because it allows me to have steering at full lock without any rubbing:

What size wheel and tire you running? I'm also considering getting the HARD ducts but concerned about rubbing. Im running 18x9.5 et35 with 265/35/18

[ugaexploder]

Bringing this one back again.

I am replacing my front wheel bearings and hubs, and it seems like this would be the time to install a backing plate with provisions for a cooling duct.

I kind of like the way the speed engineering kit uses the existing brake cooling ducts. https://www.speedengineering.de/en/p...-complete-set/

Anyone have first hand experience with this kit? Any big advantages the Hard Motorsport kit has over the Speed Engineering kit?

D-O

getting a lot of stuff done in the offseason 👍

[eacmen]

Seriously thinking of moving from brake ducts to this air dam. I've seen data at the track convincing me it might be a better solution. The one downside is you can't block them off for cold weather track days.

https://vorshlag-store.com/products/vorshlag-bmw-e46-m3-brake-cooling-deflector-kit

[ethan]

Seriously thinking of moving from brake ducts to this air dam. I've seen data at the track convincing me it might be a better solution. The one downside is you can't block them off for cold weather track days.

https://vorshlag-store.com/products/...-deflector-kit

Check out Bry5on's 3D printable design in his build thead:

https://nam3forum.com/forums/forum/main-forum/member-build-journals/195928-black-tan-332it?p=255180#post255180

I don't have data from mine yet, but they're way more convenient than my previous convoluted 3" hose setup.

[cobra]

A friend of mine who was a race engineer for many years said brake cooling is something people often overlook, and it might be one of the most important factors. Even the biggest most badass rotors/calipers eventually soak with heat and if it cannot be expelled, you're at the limit. I wonder how stock brakes with good pads and all the cooling would perform on our cars compared to a BBK with no added ducting.

[eacmen]

Check out Bry5on's 3D printable design in his build thead:

https://nam3forum.com/forums/forum/main-forum/member-build-journals/195928-black-tan-332it?p=255180#post255180

I don't have data from mine yet, but they're way more convenient than my previous convoluted 3" hose setup.

that's awesome. do you know if the STLs are shared anywhere?

[eacmen]

A friend of mine who was a race engineer for many years said brake cooling is something people often overlook, and it might be one of the most important factors. Even the biggest most badass rotors/calipers eventually soak with heat and if it cannot be expelled, you're at the limit. I wonder how stock brakes with good pads and all the cooling would perform on our cars compared to a BBK with no added ducting.

Its a double edged sword. During cold events if i have the ducts wide open I can't keep heat in them!

[cobra]

Its a double edged sword. During cold events if i have the ducts wide open I can't keep heat in them!

Interesting, never thought of that! Bet it depends on the track too.

[ethan]

that's awesome. do you know if the STLs are shared anywhere?

https://nam3forum.com/forums/forum/main-forum/member-build-journals/195928-black-tan-332it?p=279536#post279536