KNSBrakes

The air ducted to the rotor is supposed to aim at the vane entry so it goes through the rotor not around it from the back.

And it's a tough package to design and fab for low $$.

Bill Dearborn

There are products on the market that do some of what you say. Various spindle duct designs direct air into the center of the rotor where it is distributed through the center of the rotor. Some do it better than others. Here is a video of the PFC Caliper that routes air to both sides of the caliper:
Bill

Hi Volts Z06

Air flows through the center of the rotor and through the vanes at the outer edges so it cools from the inside of disk out.

JRitt@essex

A proper brake duct system is designed to cool the entire disc. It does so by funneling air into the center of the disc, NOT by blowing air on the inner half of the disc. A quality racing disc has directional vanes (and many of them). When air is fed into them, heat radiates into the air as it moves through the disc, and the heat is drawn out towards the outer circumference (see illustration below).



Blowing air directly on the inner disc half can lead to a hot outer disc and cool inner disc. Temperature gradients create cracking! A proper design forces air into the center of the disc, and 'spills' as little as possible onto the inner disc face. Below is one of our Essex / AP Racing brake kit with an integrated duct provision. Note how it blows the air directly into the center of the disc, and there's no where else for it to go:




Some systems use multiple cooling ducts. They may have one or two that feed into the disc. That depends on how much air can be grabbed from the front or under the car, then carried back to the disc. NASCAR Cup systems for example also use small electric fans to achieve the above. Rather than relying on air pressure gathered at the front or under the car, a high cfm fan forces air through the duct system.

Finally, some high-end racing calipers (such as the AP Racing Radi-CAL pictured below) also have an air duct integrated into the caliper bridge. In those systems air is also pushed by a separate duct across the top of the caliper, and down between the outer caliper pistons, providing additional piston/fluid cooling.

This is the spec AP Racing caliper used in German Touring Car (DTM):

R_W

Ok, so it seems like the best marketed systems do not cool the face of the rotors, but force air into the guts (vanes) of the rotors themselves. I can see how this would be far more efficient than simply blowing air onto the face of the inside rotor.
That would also solve the issue I thought of with the rotor-style design of airflow to the outside face of the rotor being minimal.

I love this forum. Such a wealth of knowledge everywhere you look.

R_W

JRitt,

This is genius! This will do the trick. Does Essex / AP sell just the duct / rotor attachment piece?
If not, is there a kit available for the C6 Z/GS brakes that includes that duct/piece? I use blanks on the track to keep costs down (cracks happen, as we all know, it is just a matter of time), and if I can keep from paying crazy money for pads / rotors (along the lines of ceramic rotors, etc), I'm happy. So if I need to buy a kit, hopefully it is something with easily replaceable rotors.
Hopefully Essex/AP can meet my needs on this!

0Todd TCE

A properly designed brake duct is NOT designed to cool only one side of the rotor. Those that blow air on the back of them are poorly designed and create pad wear and temperature problems more than do a lot of good.

A well designed kit is pretty much as you stated: vented into the rotor. A totally encapsulated one is ideal as it forces the air into the center of the disc where the internal vanes, vents, air channels etc expel it equally throughout the inside of the casting.

*Should you be confused; those vents don't scoop air from it's outside but pump it inside to the outside.

Here's a random goodle image:

R_W

^^ Does anyone offer something like this for the C6?

FASTFATBOY

Blaine makes them I'm sure. I know hemakes them for F bodies and C5's

Blaine Fabrication

http://www.blainefabrication.com/

Glenn Pieschke

GM says to replace your ceramic rotors if ANY slight groove or chip! Is this really necessary or is this just an attempt to sell more expensive parts???
I do a lot of track days with my ZR1 (8,000 track miles); watch my pad wear but the pad base plate caused a few thousandths groove near the hat, by the time the "change pads" light came on. Is it really dangerous or is this just a CYA by GM??? I would think that someone may have scored a rotor and continued running fine??? Also the owners manual says to replace when the weight drops miniscual or if there is a "half mm thickness wear" (i.e. 36mm original......replace if 35.5 mm thick). Again is this overkill and how much reserve is built in??? With all this hype, and all the track days our members participate, has anyone had or really known of a C6 or C7 rotor failure (shatter or disintegrate)???

phipp85

On my first set of rotors I ran one pad down to the backing plate(rear) BUT the pad didn't have any uneven wear. I felt it when it happened and came right in. I put a new set of pads in and kept on running. If you had it happen on a pad with a lot of taper it may have dug a bit of a trench into the disc face.

phipp85

We need these for the corvette kits!!!!

Bill Dearborn

I suspect Brembo set that standard not GM. I don't know how Ceramic Rotors fail in the extreme but I suspect Brembo knows. The manufacturing process obviously has some variation in it since minimum weights vary from one rotor to the next. Minimum thickness is the same for all rotors. The way the rotors are made which includes heating them to very high temperatures several times suggests they are hardened and may be more subject to damage than softer materials. Just like a hardened eye glass lens provides impact protection to the person wearing the lens the lens is also much easier to scratch with simple things like tissues or a handkerchief.

Bill

ghickenlooper

I am working on a 1988 C4 with I think is an ABS problem. I have replace the master cylinder, all 4 sets of pad and my problem continues. When breaking it feels like the ABS is preventing me from fully pushing the break down, it has a back pressure and I have to push harder to get a solid stop. It also has a sound like leaking air when the break pedal is pushed. Looking for Ideas and help. Thanks

Hi Volts Z06

Power brake booster?

bandit666

I'm currently swapping the d44 IRS from my 86 parts car into my built 87 that I'm going to drag race.The 87 is a 383 stroker,carb putting out 488 hp to the wheels.I'm hoping to be in the high 11s or low 12s.I want to upgrade the brakes to maybe a c5 set up or whatever is the least expensive as I'm about out of money for this build.Any help on what I'll need and where to get it will be greatly appreciated.Emphasis on as low cost as possible.

Twiggs

Quick question for you guys.

Is is possible or dangerous to run a autoX / HPDE spec front pad, and keep the rear pads a street material? This would be on a stock brake system C6 coupe, and hypothetically a CP8350 front kit from AP.


Disclosure: The reason for this is because I'm lazy and would rather pop the road pads out and pop the track pads in, rebed the pads and call it a day if I'm going to be heading down to the Glen for a track day.

froggy47

Guys smarter than me will probably respond, but just so you know there is quite a difference between an autox pad and a track pad, so get the right one for your use.

TKOGTO

I did many times without issue but always tried to balance everything the best I could. For example, match your pads to your tires. If on street tires, don't overpower them with very aggressive track pads, e.g. ST-47s, DTC 70s, or XR1s. Second, along the lines of #1, limit the difference between the TQ/CoF between the fronts and rears.

Many run a less aggressive set in the rear, the key is not too great of a difference.

wtb-z

I generally run a race pad in the front and HP+ in the rear of my C5 Z06. In addition to being something else to not change for the track day, rear rotor life with the HP+ seems to approach "forever".

Edit, not related to your question exactly - but I will say that running a street pad in the front, a race pad in the rear, and with the ECBM module on the workbench back home is not a good idea.