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.2RS Added Brake Cooling = trackable PCCBs?

 
Old 05-09-2018, 04:47 PM
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sorry 1 pound unsprung = 15.5 lbs spung equivalent. so 620 lbs total at all 4 corners.
We also need to include the performance increase do to less rotational mass of the rotor.

Last edited by mcipseric; 05-09-2018 at 05:07 PM.
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Old 05-09-2018, 07:04 PM
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I’ve had PCCB and iron and I prefer CCB for suspension feel and less pedal effort. The car feels lighter and more controlled on bumps, which at Sebring matters, other tracks maybe not so much. Stopping is ultimately limited by the tires but the better initial bite and lower pedal effort means I feel less beat up at the end of the weekend. I think initial bite of PCCB is better than OEM pad’s but so is Ferodo/AP rotor combo, so not sure how big a difference it will make over my normal track setup. I think the reason to do ST CCB is lower unsprung weight since rebuild cost seems comparable to iron.
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Old 05-09-2018, 07:38 PM
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Originally Posted by TRAKCAR View Post
Love GR / gold! Such a special combo and comes as-is.
Agreed Peter. I was only sold on it after watching the videos and seeing the pictures. The combo really looks great. A bit old school but so am I.
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Old 05-09-2018, 10:24 PM
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Originally Posted by mcipseric View Post
sorry 1 pound unsprung = 15.5 lbs spung equivalent. so 620 lbs total at all 4 corners.
We also need to include the performance increase do to less rotational mass of the rotor.
Now there is some bogus math. Acceleration-wise, removing mass at the wheels is equivalent to 2-2.5x max. So 1 lb = 2 to 2.5 pounds.

Bump rebound dynamics is a different story.
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Old 05-10-2018, 02:12 AM
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Originally Posted by whatif
It's interesting, but I don't know if there's any data to support that PCCBs stop better. In theory the stopping distances should be same for both brakes with the limiting factor being the tires. The iron brakes should be able to provide the same amount of brake torque, just less thermal efficiency. Is it possible that it's the mental factor of you thinking that you have better brakes with PCCBs being more confidence inspiring, so you're more comfortable going deeper into the braking zone?
It's been covered before on the forum, with articles referenced where direct comparisons were made. Im not going to look up the threads or articles now, but the answer is that pccb offer more consistent fade-free performance than iron, but braking distances are the same.

The golden ticket now seems to be to spec your car with irons then buy ST rotors.
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Old 05-10-2018, 03:40 AM
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Originally Posted by CAlexio View Post
It's been covered before on the forum, with articles referenced where direct comparisons were made. Im not going to look up the threads or articles now, but the answer is that pccb offer more consistent fade-free performance than iron, but braking distances are the same.

The golden ticket now seems to be to spec your car with irons then buy ST rotors.
Couldn't another option be spec with PCCB (higher resale value) and put on ST Rotors?
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Old 05-10-2018, 10:38 AM
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Originally Posted by SCCAForums View Post
Couldn't another option be spec with PCCB (higher resale value) and put on ST Rotors?
yes, I think someone should do a comparison of for sale RS’, otherwise same optioned but iron versus PCCB and determine if the investment return is greater than putting the $9k in the market. That would really help me make a decision! 🤪
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Old 05-10-2018, 06:23 PM
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Originally Posted by CDinSing View Post


yes, I think someone should do a comparison of for sale RS’, otherwise same optioned but iron versus PCCB and determine if the investment return is greater than putting the $9k in the market. That would really help me make a decision! ��

Most likely there is no "return" on the 9k investment. The return is at best 0, if not negative.

A PCCB RS should sell for more, but not more than the cost of the option.
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Old 05-10-2018, 06:24 PM
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Originally Posted by Mech33 View Post


Now there is some bogus math. Acceleration-wise, removing mass at the wheels is equivalent to 2-2.5x max. So 1 lb = 2 to 2.5 pounds.

Bump rebound dynamics is a different story.
That sounds a lot more like it
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Old 05-11-2018, 01:33 AM
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Originally Posted by whatif View Post
Most likely there is no "return" on the 9k investment. The return is at best 0, if not negative.

A PCCB RS should sell for more, but not more than the cost of the option.
I think this is right, what I meant was more along the lines with an RS (or a GT3 for that matter) it seems the 'asking price' is always 'based on' the MSRP of the car... so while you may not 'get more'... you don't 'get less'... and you typically have a broader audience (appeal) to sell the car.

If you're never selling the car, tracking exclusively, then no need... but if you're only keeping until the 'next one' comes along... some of the options are more important for mass appeal (IMO).

Best Regards,
Dave
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Old 05-11-2018, 09:12 AM
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Originally Posted by GrantG View Post
OEM calipers are same, except the body of the yellow calipers has a shape that acts similar to an integrated spacer which lets it work with the larger diameter rotors. It is not possible to use the smaller iron rotors with PCCB calipers for this reason, but you can add a spacer to the red calipers to work with larger rotors.
Thanks Grant...so how are these guys that get PCCB using iron rotors? I’m guessing there are aftermarket iron rotors...bigger than stock own gt3 rotors....that fit the PCCB caliper?
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Old 05-11-2018, 11:41 AM
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Originally Posted by mdrums View Post

Thanks Grant...so how are these guys that get PCCB using iron rotors? I’m guessing there are aftermarket iron rotors...bigger than stock own gt3 rotors....that fit the PCCB caliper?
Correct - you need to use some manhole covers (410mm front 390mm rear iron rotors - OEM irons are 380/380 mm) - Girodisc is one of the more common options:

http://www.girodisc.com/Girodisc-Fro...rs_p_6677.html

http://www.girodisc.com/Girodisc-Rea...rs_p_6678.html
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Old 05-11-2018, 11:44 AM
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I wonder what the total weight difference is per corner for the worst case scenario (20-21" std wheels with MPSC and extra large steel rotor from PCCB concersion) VS best case scenario (Magnesium wheels / 19" wheels with Hoosiers and PCCB rotors).
Someone should weigh it out.
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Old 05-11-2018, 01:35 PM
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Originally Posted by TRAKCAR View Post
I wonder what the total weight difference is per corner for the worst case scenario (20-21" std wheels with MPSC and extra large steel rotor from PCCB concersion) VS best case scenario (Magnesium wheels / 19" wheels with Hoosiers and PCCB rotors).
Someone should weigh it out.
My understanding is that the Girodiscs are very similar in weight to the standard steels even though they are larger diameter.
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Old 05-17-2018, 05:43 PM
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Originally Posted by usctrojanGT3 View Post
What about brake pads...didn't you have to get different pads for the ST rotors vs. the steel rotors?
Pagid pad shape for the factory iron rotors (380 F/R) is 4924 F and 4945 R. On a conversion to our ST ceramic rotors (410 F/400 R) the pad shape on the front changes to 4927 (the same as factory PCCB equipped cars) and the rear stays the same at 4925 (also the factory PCCB equipped shape).
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