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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
I am looking for some feedback from those running the AP Racing two piece rotors on track. I recently installed the AP Racing Radical front calipers and 355mm 2 piece rotors on my 2011 C6 Grand Sport. I currently have Quantum backing plates and hoses that connect to the factory tubing which directs air from under the front splitter. However, I have been told by some others at the track that the backing plates and tubing can actually hinder the cooling of the rotors. They claim that that the rotors are designed to pump huge volumes of air and that the backing plates hinder that. In addition, the flattened area in the factory ducting which is designed not to rub the tire can't flow the actual volume of air needed. They suggested I would do better to remove the backing plates to let the rotors breathe/pump air and remove the flexible tubing to allow the factory ducting to circulate fresh air into the area. I have only one day on the new brakes and they were awesome with no fading. (but it was a cool weekend.) There is some minor crazing in the center of the rotors so I am concerned about their longevity if not properly cooled. When I called Essex to ask all they could say is that they have heard of good and bad experiences both with and without added cooling. What have been your real experiences with cooling for these rotors on the track? Thanks!!
If you want more info, PM me with your normal e-mail address and I can send you a lot more info. I now run Wilwood Aero6 front calipers with Wilwood GT72 two-piece rotors on the track.
some people add high volume electric fans into the ducting when coming off the fog lights.
IMO, you DO want the spindle ducts.
Faded my AP brake setup once before adding the spindle ducts.
I am looking for some feedback from those running the AP Racing two piece rotors on track. I recently installed the AP Racing Radical front calipers and 355mm 2 piece rotors on my 2011 C6 Grand Sport. I currently have Quantum backing plates and hoses that connect to the factory tubing which directs air from under the front splitter. However, I have been told by some others at the track that the backing plates and tubing can actually hinder the cooling of the rotors. They claim that that the rotors are designed to pump huge volumes of air and that the backing plates hinder that. In addition, the flattened area in the factory ducting which is designed not to rub the tire can't flow the actual volume of air needed. They suggested I would do better to remove the backing plates to let the rotors breathe/pump air and remove the flexible tubing to allow the factory ducting to circulate fresh air into the area. I have only one day on the new brakes and they were awesome with no fading. (but it was a cool weekend.) There is some minor crazing in the center of the rotors so I am concerned about their longevity if not properly cooled. When I called Essex to ask all they could say is that they have heard of good and bad experiences both with and without added cooling. What have been your real experiences with cooling for these rotors on the track? Thanks!!
I have the Essex AP Endurance Kit F and R. Quantum cooling kit F. Best brakes I have used on a street car based platform. No issues so far in 2 seasons. No soft pedal and no fading ever. Brake pad wear is very reasonable. Rotors are still the originals that came with the kit. I have no intention of removing the Quantum kit.
You need to change the stock duct over to one that will fit the hose better. I changed mine over to the LG duct that has a metal outlet that let me attach a standard red brake hose to it. Then I attached the other end to the Quantum duct. I also did some modification to the Quantum Duct. If you look where the hose attaches to the duct you will notice the piece of tubing is open to the rear. Air comes into the tubing and then can easily exit toward the inside of the wheel well Vs going through the rotor. I used some aluminized duct tape to seal off the opening so the air coming through the ducts had to exit through the rotor.
You need to change the stock duct over to one that will fit the hose better. I changed mine over to the LG duct that has a metal outlet that let me attach a standard red brake hose to it. Then I attached the other end to the Quantum duct. I also did some modification to the Quantum Duct. If you look where the hose attaches to the duct you will notice the piece of tubing is open to the rear. Air comes into the tubing and then can easily exit toward the inside of the wheel well Vs going through the rotor. I used some aluminized duct tape to seal off the opening so the air coming through the ducts had to exit through the rotor.
Bill
See Post #2 link for a great brake cooling solution. I can provide more info to a PM with normal e-mail address. I modified the stock OEM plastic outlet to full 3" and the inlet from the grill sides is 4".
The Quantum duct opening is intended to help cool the wheel bearings and I have not blocked that off.
The only way the duct kit is making things worse is if it's not sealed up well. You want all the air coming in to go to the center of the rotor.
I agree with all the above comments except the one about cooling the wheel bearing. I believe you should tape that section up like Bill described. I also have the ducts feeding from the front grill as AZDave47 linked in post #2. My setup is slightly different with 3" ducting instead of 4" as I was concerned with overcooling the disc on the long straights. Disc temps are where they should be for now but I have not ran the current setup in the middle of the summer yet.
Get yourself some temperature indicating paint and you will easily be able to tell if your cooling setup is working for you or not. I have the AP racing disc temp kit. 3 colors in it, green, orange and red.
I did the same thing that AZdave mentioned. I have 4 inch ducts going straight to the rotors. I did have the stock set up with the quantum ducts, but wasn't getting me through the session without brake fade in the spring/summer months. My engine temperatures didn't see much of a difference with the front grille being modified.
If you want more info, PM me with your normal e-mail address and I can send you a lot more info. I now run Wilwood Aero6 front calipers with Wilwood GT72 two-piece rotors on the track.
PS, that is a great set of front brakes you have.
Dave, can you email me the info about the brake cooling mod that JDIllon did
keep the quantum spindle ducts.
im also running the quantum fog ducts.
the factor inlet under the car is pretty useless.
lol I like how you sealed up the brake ducts with tape because i did the same thing! mine has held up so far and it's been through 1 season of summer and rain.
yep. $4
i bought some of the $150 brake duct hose to do it right the first time on my SS. but it was so stiff and thick, it simply could not make the bends needed inside the wheel. so i ran to lowes and picked up dryer hose. tracked the car every month (some times twice in summer) for a year and never had an issue. worked great. lighter too.
its more like chrome plastic sheet, than the old aluminum stuff.
i reinforce the ends with duct tape (so the hose clamps dont cut it)
worked great.
Last edited by STANG KILLA SS; 04-14-2017 at 06:22 PM.
Dave, have you been happy with the Aero6 brake setup?
Thanks,
Yes, I like them. I haven't gone thru a full set of track pads yet, but even in 100* heat on a short track they worked fine and I'm sure they don't have the taper wear the OEM calipers have. The Wilwood street pads work fine, too. You do have to install the Wilwood SS brake lines as the fluid inlet fitting is not a banjo bolt setup but a pipe thread.
While I run the car hard on track days I'm not concerned about the last second or so. If I was a heavy track junky (retired racer now) I'd move up to a more track focused setup. That setup from Essex was really impressive.
Even with the Aero6 calipers and Wilwood GT72 front rotors for the track, I am glad I have the 4" front duct cooling with 3" out to the rotors. The OEM cooling just does not get enough cool air to the rotors.
03-28-2017, 06:33 PM
Brake Ducts or NO Brake Ducts?
