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      11-20-2019, 02:05 PM   #23
Kev608
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I just scored the deal of the year! $550 shipped (the cheapest I could find these was over $1,200) for four sets of pads? Ok.

https://www.ebay.com/itm/Bundle-of-D...app-cvip-panel

Last edited by Kev608; 11-20-2019 at 02:10 PM..
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      11-20-2019, 02:49 PM   #24
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CCB (gold) brake calipers:
Front 6 pistons: 30/34/36mm = 52.7 cm^2 (68%)
Rear 4 pistons: 28/28mm = 24.6 cm^2 (32%)
Total: 77.4 cm^2
Iron (blue) brake calipers:
Front 4 pistons: 40/40mm = 50.3 cm^2 (67%)
Rear 2 pisotns: 40mm cm = 25.1 cm^2 (33%)
Total: 75.4 cm^2
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      11-20-2019, 03:00 PM   #25
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Quote:
Originally Posted by DavidStr View Post
CCB (gold) brake calipers:
Front 6 pistons: 30/34/36mm = 52.7 cm^2 (68%)
Rear 4 pistons: 28/28mm = 24.6 cm^2 (32%)
Total: 77.4 cm^2
Iron (blue) brake calipers:
Front 4 pistons: 40/40mm = 50.3 cm^2 (67%)
Rear 2 pisotns: 40mm cm = 25.1 cm^2 (33%)
Total: 75.4 cm^2
What is the source of this info though? A search of listed parts showed the rear calipers have 44mm pistons.

Actually, I managed to find parts listed for the rear at 40mm as well. Might grab the calipers and measure mine.

Last edited by Kev608; 11-20-2019 at 03:23 PM..
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      11-20-2019, 03:32 PM   #26
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I have done plenty of digging when I was evaluating Ceika, Ksport BBK.
I have constantly found 40mm piston size

https://www.racingbrake.com/category-s/7567.htm

https://www.racingbrake.com/Piston-K...2-p/bb-22p.htm
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      11-24-2019, 01:48 PM   #27
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I ordered the BBK today. The total with their Black Friday deal came out to $4,316. With the two sets of Hawk DTC pads all around, I'm under $4,900! I'll post un-boxing, install, and review videos once I've got them.
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      11-26-2019, 03:24 PM   #28
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Great, let us know how it goes! thanks for sharing!
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      11-27-2019, 07:42 PM   #29
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Quote:
Originally Posted by Kev608 View Post
AP Racing is another popular choice, though well out of my price range.

Front piston area of 9960/9968 = 5,022mm≤
Rear piston area of 9449 = 3,101mm≤

This is almost the same front area with a very slight bump up in the rear.

Also, keep in mind that they use a smaller rear disc, meaning you'll have less stopping power in the rear.
Thatís not exactly true. The mean radius of the brake rotor ring is used when calculating brake torque. Assuming pads with the same COF are used in the stock and AP Radi-CAL caliper then AP CP9449 caliper + 365 mm OD rotor with a 42 mm radial pad depth results in a mean rotor radius of 140 mm. The stock rear iron rotor OD is 370 mm and the pad radial depth is ~70 mm (not defined on pad cross section and I donít have a pad handy to measure it but itís at least 70 mm) so the stock rear mean radius is approximately 115 mm. Ratio of AP rear brake torque to Stock rear brake torque is Apiston_ap*Rmean_ap /Apiston_oem*Rmean_oem assuming pads with equal COF and equal brake line pressures. Assuming your piston area calculations are correct, Brake Torque Ratio = (3101 mm^2*140 mm) / (2501 mm^2*115 mm) = 434130 mm^3 / 287615 mm^3 = 1.51 - the AP 9449/365 mm setup has higher brake torque capability than stock even though it uses a rotor with a smaller OD than the stock rotor OD.
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      11-27-2019, 11:19 PM   #30
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Quote:
Originally Posted by M3SQRD View Post
Thatís not exactly true. The mean radius of the brake rotor ring is used when calculating brake torque. Assuming pads with the same COF are used in the stock and AP Radi-CAL caliper then AP CP9449 caliper + 365 mm OD rotor with a 42 mm radial pad depth results in a mean rotor radius of 140 mm. The stock rear iron rotor OD is 370 mm and the pad radial depth is ~70 mm (not defined on pad cross section and I donít have a pad handy to measure it but itís at least 70 mm) so the stock rear mean radius is approximately 115 mm. Ratio of AP rear brake torque to Stock rear brake torque is Apiston_ap*Rmean_ap /Apiston_oem*Rmean_oem assuming pads with equal COF and equal brake line pressures. Assuming your piston area calculations are correct, Brake Torque Ratio = (3101 mm^2*140 mm) / (2501 mm^2*115 mm) = 434130 mm^3 / 287615 mm^3 = 1.51 - the AP 9449/365 mm setup has higher brake torque capability than stock even though it uses a rotor with a smaller OD than the stock rotor OD.
Thank you! I didn't know this. Does the width of the pad not matter? Obviously the stock pads are deep, but not very wide. I feel like I need to do the real math here. I'm a science guy and I feel like these companies aren't just pulling these specs out of thing are. It seems there is a lot of variation from kit to kit though.
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      11-28-2019, 12:34 AM   #31
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Quote:
Originally Posted by Kev608 View Post
Thank you! I didn't know this. Does the width of the pad not matter? Obviously the stock pads are deep, but not very wide. I feel like I need to do the real math here. I'm a science guy and I feel like these companies aren't just pulling these specs out of thing are. It seems there is a lot of variation from kit to kit though.
The PFC Z54 4-piston F caliper uses the PFC 7836 pad profile (28 mm-thick, 52 mm-radial depth)) and a 372 mm rotor whereas the AP 9449 F 6-piston caliper uses the PFC 7790 profile (25 mm-thick, 54 mm-radial depth) and a 372 mm rotor. The 7790 has more pad area than the 7836 (see links below for pad profiles) yet both brake kits have very similar overall brake performance, fade resistance, modulation and release characteristics (I have the PFC z54/z45 brake setup on my E92 M3 and the Essex/AP CP9668/CP9449 brake setup on my F82 M4, and I use the PFC 11 pad compound on the F and R except for the 9449 R caliper which isnít offered in the 11 compound so I use PFC 05 and 03, 01 if 05/03 isnít available). Pad surface area has a secondary effect on brake torque.

Top race brake caliper and pad manufacturers will typically shift the brake bias toward the rear a bit on a street/track car which will improve overall braking performance on a car thatís been moderately lowered using quality dampers with higher than stock spring rates, is corner balanced (shallow rake) and running gripper r-comp/race tire compounds. These changes make the rear brakes more effective; i.e., contribute more to overall braking performance.

PFC 7736: https://pfc.parts/product/7836/

PFC 7790:
https://pfc.parts/product/7790/
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      11-28-2019, 11:12 AM   #32
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With the DTC-60 rear and DTC-30 front, I should have a pretty well balanced bite given the 1.24:1 piston size ratio. Also, the rear pads are 3mm thicker, but more than twice the price of the fronts. I may consider a different rear pad for this reason.
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      12-06-2019, 03:54 PM   #33
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any news on this ?
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      Yesterday, 01:41 PM   #34
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Quote:
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any news on this ?
I am waiting for them to ship. Apparently it takes a couple of weeks for them to manufacture and ship these kits, since they are built to order.
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