997 vs 991 Brakes
11-25-2016, 03:25 PM
#1
997 vs 991 Brakes
I have read several old threads comparing 997 to 991 Cups and I noticed that more than one poster commented on how the 997 brakes were a weak spot that was corrected on the 991.
For my continuing education, can some of the "sages" on here fill me in on 1. What were the problem with the 997 brakes and 2. What changes did Porsche make on the 991 to rectify the situation.
As always, I appreciate any information.
Don
For my continuing education, can some of the "sages" on here fill me in on 1. What were the problem with the 997 brakes and 2. What changes did Porsche make on the 991 to rectify the situation.
As always, I appreciate any information.
Don
11-25-2016, 03:43 PM
#2
Burning Brakes
The 997 Cup (either .1 or .2) brakes are not bad. They're just tricky to get 100% performance out of because they need excellent technique and mistakes reveal themselves immediately. It's also what makes them the best for learning the proper fundamentals, IMO.
The 991 Cup brakes are similar in that they take very solid fundamentals to work at the best. The 991 Cup chassis is much improved over the 997 so that helps the braking ability and stability more than any real changes in the brake system itself.
-mike
The 991 Cup brakes are similar in that they take very solid fundamentals to work at the best. The 991 Cup chassis is much improved over the 997 so that helps the braking ability and stability more than any real changes in the brake system itself.
-mike
11-26-2016, 01:10 AM
#3
Advanced
+1 to what Mike said.
I wouldn't call the calipers on the 997 weak in general. They do get softer as they get hot and if you don't run the ti endurance piston kit, you will see uneven pad wear and generally more wear within the caliper body. The calipers do wear out after a season or two of heavy use and need to be replaced. You'll start to see significant wear in the housing where the pistons sit.
The 991 calipers are a much stiffer body and a true racing caliper rather than a road caliper adapted for racing. Generally more confidence inspiring. You can brake deeper with a 991 as the brakes are much better, but so is the chassis and wider tire contact patch. The Cayman Clubsports have been able to take advantage of the PFC brakes as well, outbraking 997's and even 991's, while running smaller tires.
The 997 gives much more feedback as the car is approaching the limit, but getting to 90-95% is much harder compared to the 991. However, getting that last 5-10% out of a 991 is MUCH more challenging than a 997 as the 991 is so numb in feedback, including under braking, so the feeling of everything being under control in the 991 is a little contrived. YMMV.
Cheers
Mark
I wouldn't call the calipers on the 997 weak in general. They do get softer as they get hot and if you don't run the ti endurance piston kit, you will see uneven pad wear and generally more wear within the caliper body. The calipers do wear out after a season or two of heavy use and need to be replaced. You'll start to see significant wear in the housing where the pistons sit.
The 991 calipers are a much stiffer body and a true racing caliper rather than a road caliper adapted for racing. Generally more confidence inspiring. You can brake deeper with a 991 as the brakes are much better, but so is the chassis and wider tire contact patch. The Cayman Clubsports have been able to take advantage of the PFC brakes as well, outbraking 997's and even 991's, while running smaller tires.
The 997 gives much more feedback as the car is approaching the limit, but getting to 90-95% is much harder compared to the 991. However, getting that last 5-10% out of a 991 is MUCH more challenging than a 997 as the 991 is so numb in feedback, including under braking, so the feeling of everything being under control in the 991 is a little contrived. YMMV.
Cheers
Mark
11-26-2016, 12:56 PM
#5
Thanks for the replies.
I am going over my car top to bottom in an attempt to try and address known "weak" areas and to add a few upgrades here and there without going too crazy.
From your comments, it sounds like the 997 brakes can be made to equal the 991 brakes with a caliper change, but braking performance per se will still be
limited by chassis and contact patch in comparison. I can live with that.
It also sounds like I'll have my work cut out learning how to get the most out of my brakes. Probably going to have a hefty tire bill until I get a handle on it.
Thanks again.
Don
I am going over my car top to bottom in an attempt to try and address known "weak" areas and to add a few upgrades here and there without going too crazy.
From your comments, it sounds like the 997 brakes can be made to equal the 991 brakes with a caliper change, but braking performance per se will still be
limited by chassis and contact patch in comparison. I can live with that.
It also sounds like I'll have my work cut out learning how to get the most out of my brakes. Probably going to have a hefty tire bill until I get a handle on it.
Thanks again.
Don
11-30-2016, 03:03 AM
#6
+1 to what Mike said.
I wouldn't call the calipers on the 997 weak in general. They do get softer as they get hot and if you don't run the ti endurance piston kit, you will see uneven pad wear and generally more wear within the caliper body. The calipers do wear out after a season or two of heavy use and need to be replaced. You'll start to see significant wear in the housing where the pistons sit.
The 991 calipers are a much stiffer body and a true racing caliper rather than a road caliper adapted for racing. Generally more confidence inspiring. You can brake deeper with a 991 as the brakes are much better, but so is the chassis and wider tire contact patch. The Cayman Clubsports have been able to take advantage of the PFC brakes as well, outbraking 997's and even 991's, while running smaller tires.
The 997 gives much more feedback as the car is approaching the limit, but getting to 90-95% is much harder compared to the 991. However, getting that last 5-10% out of a 991 is MUCH more challenging than a 997 as the 991 is so numb in feedback, including under braking, so the feeling of everything being under control in the 991 is a little contrived. YMMV.
Cheers
Mark
I wouldn't call the calipers on the 997 weak in general. They do get softer as they get hot and if you don't run the ti endurance piston kit, you will see uneven pad wear and generally more wear within the caliper body. The calipers do wear out after a season or two of heavy use and need to be replaced. You'll start to see significant wear in the housing where the pistons sit.
The 991 calipers are a much stiffer body and a true racing caliper rather than a road caliper adapted for racing. Generally more confidence inspiring. You can brake deeper with a 991 as the brakes are much better, but so is the chassis and wider tire contact patch. The Cayman Clubsports have been able to take advantage of the PFC brakes as well, outbraking 997's and even 991's, while running smaller tires.
The 997 gives much more feedback as the car is approaching the limit, but getting to 90-95% is much harder compared to the 991. However, getting that last 5-10% out of a 991 is MUCH more challenging than a 997 as the 991 is so numb in feedback, including under braking, so the feeling of everything being under control in the 991 is a little contrived. YMMV.
Cheers
Mark
I also liked the brakes on the 997 better because you could be so aggressive with them and on the downshifts.
991 performance way higher without question
07-31-2017, 11:28 AM
#7
Former Vendor
Questions from RacingBrake:
1. Has anyone tried to figure out why it's more difficult to get feedback and harder on brake release (on a 991 vs. 997 Cup).
2. Are you allowed to replace a brake component to aftermarket, and if so what replacement/upgrade you are considering.
In our recent CCM brake system build for David Donohue (A combination of Trubo S and Cup), and with great help from Bob Faieta - Competition Motorsports, we have a pretty good understanding on 991 Cup brakes resulting our full development of both iron and carbon ceramic rotors and sintered brake pads (trim to fit PFC calipers), and the complete brake system including 6 pot front and 4 pot rear forged aluminum alloy calipers.
We also have brake replacement components and complete brake system upgrade for 997 Cup.
1. Has anyone tried to figure out why it's more difficult to get feedback and harder on brake release (on a 991 vs. 997 Cup).
2. Are you allowed to replace a brake component to aftermarket, and if so what replacement/upgrade you are considering.
In our recent CCM brake system build for David Donohue (A combination of Trubo S and Cup), and with great help from Bob Faieta - Competition Motorsports, we have a pretty good understanding on 991 Cup brakes resulting our full development of both iron and carbon ceramic rotors and sintered brake pads (trim to fit PFC calipers), and the complete brake system including 6 pot front and 4 pot rear forged aluminum alloy calipers.
We also have brake replacement components and complete brake system upgrade for 997 Cup.