C5 brake upgrade w/ stock size wheels. Good preferences?
02-21-2012, 02:21 PM
#21
Safety Car
Member Since: Nov 2000
Location: Shenandoah Valley Virginia
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The diameter of the Y2K wheels will be fine, it's the caliper to spoke clearance that will be a problem. A spacer is required. C5 Z06 wheels fit fine over the Wilwood kit without clearance problems. If the much larger front caliper is used on the rear, there is a proportioning problem Do a search, there have been several detailed threads on this subject.
02-21-2012, 03:53 PM
#22
Drifting
from this thread: http://forums.corvetteforum.com/c5-t...of-brakes.html
My $0.02:
I am using ceramics even though they don't have as much bite as the stockers. For an occasional panic stop - they're great. Considering the lifespan, lack of dust and performance for a daily driver - they may be a good choice. If you only take your car out on beautiful days and drive it hard the whole time - they may not be for you. For repeated high speed stops, they grenade and look like this:
The only thing more friction at the rotors does is reduce the amount of brake-pedal pressure required for the same amount of braking power.
If a low friction pad still has enough friction with the rotor to overcome the tires' traction limit, then the tires become the "weakest link".
ABS has no effect on which pad will be more effective. ABS simply relieves brake pressure when the tires begin to skid because the driver pushes the pedal to hard. (Or the tires transition to a surface with less traction.)
Brake pads have no contact with the road. With modern disc brakes, tires are ALWAYS the limiting factor in how quickly a car can stop. (Unless the brakes are being used repeatedly and get too hot.)
The reason you feel like your high-friction pads are stopping your car better is because you don't have to push your pedal as hard for the same amount of breaking. Ceramic pads have enough friction to overcome the tires' traction threshold and engage the ABS. Just because you have to push the pedal a little harder to achieve this, doesn't mean you aren't stopping as fast.
If a brake pad has enough friction to engage the ABS (or cause the tires to skid on a car without ABS), then it is providing 100% of the stopping-power available to the car. Period. It's that simple.
So WHY do people use performance pads?
Ceramic pads don't hold-up well to high heat. If you are using your brakes repeatedly they will get too hot, and the Ceramic pads begin to loose friction. They loose so much friction that, they can no longer overcome the tires' traction threshold. I experienced this the first time I took my car to the track. My brakes got so hot that, I was pushing the pedal as hard as I could, and I still couldn't get the tires to start chirping.
To sum it all up;
Ceramic Pros:
Quite
Clean
Longer life
Ceramic Cons:
Can't cope with high-heat, repeated braking. (Track use)
Performance Pad Pros:
Can withstand the high-heat, repeated braking associated with track use.
Provide better "feel" especially when hot. (This comes back to the fact that you're not pushing on the pedal as hard.)
Performance Pad Cons:
Noisy (usually squeek or squeel more)
Dirty
Typically more expensive
Don't last as long.
Sorry for the lengthy post. I'm a mechanic, and this is kind-of a pet-peave of mine. I talk to a lot of people who have misconceptions about brakes.
If a low friction pad still has enough friction with the rotor to overcome the tires' traction limit, then the tires become the "weakest link".
ABS has no effect on which pad will be more effective. ABS simply relieves brake pressure when the tires begin to skid because the driver pushes the pedal to hard. (Or the tires transition to a surface with less traction.)
Brake pads have no contact with the road. With modern disc brakes, tires are ALWAYS the limiting factor in how quickly a car can stop. (Unless the brakes are being used repeatedly and get too hot.)
The reason you feel like your high-friction pads are stopping your car better is because you don't have to push your pedal as hard for the same amount of breaking. Ceramic pads have enough friction to overcome the tires' traction threshold and engage the ABS. Just because you have to push the pedal a little harder to achieve this, doesn't mean you aren't stopping as fast.
If a brake pad has enough friction to engage the ABS (or cause the tires to skid on a car without ABS), then it is providing 100% of the stopping-power available to the car. Period. It's that simple.
So WHY do people use performance pads?
Ceramic pads don't hold-up well to high heat. If you are using your brakes repeatedly they will get too hot, and the Ceramic pads begin to loose friction. They loose so much friction that, they can no longer overcome the tires' traction threshold. I experienced this the first time I took my car to the track. My brakes got so hot that, I was pushing the pedal as hard as I could, and I still couldn't get the tires to start chirping.
To sum it all up;
Ceramic Pros:
Quite
Clean
Longer life
Ceramic Cons:
Can't cope with high-heat, repeated braking. (Track use)
Performance Pad Pros:
Can withstand the high-heat, repeated braking associated with track use.
Provide better "feel" especially when hot. (This comes back to the fact that you're not pushing on the pedal as hard.)
Performance Pad Cons:
Noisy (usually squeek or squeel more)
Dirty
Typically more expensive
Don't last as long.
Sorry for the lengthy post. I'm a mechanic, and this is kind-of a pet-peave of mine. I talk to a lot of people who have misconceptions about brakes.
I am using ceramics even though they don't have as much bite as the stockers. For an occasional panic stop - they're great. Considering the lifespan, lack of dust and performance for a daily driver - they may be a good choice. If you only take your car out on beautiful days and drive it hard the whole time - they may not be for you. For repeated high speed stops, they grenade and look like this:
02-21-2012, 07:23 PM
#24
Le Mans Master
The diameter of the Y2K wheels will be fine, it's the caliper to spoke clearance that will be a problem. A spacer is required. C5 Z06 wheels fit fine over the Wilwood kit without clearance problems. If the much larger front caliper is used on the rear, there is a proportioning problem Do a search, there have been several detailed threads on this subject.
12-09-2016, 05:26 PM
#25
Racer
Revival
As to the original intent if this thread, I too am looking to upgrade my C5 Z06 brakes with Stock 17" wheels. I am amazed at how may "C5 upgrade kits" are available, but when you look into them, almost all require 18" wheels. I will be using the car for HPDE, not a daily driver. I have a modest budget in mind, <$3K
This is what I have found so far is:
LG G-Stop Wilwood kit.
Front only $1600, Pads included but no rotors. (already mentioned in this thread)
Pros:
20mm pads for long life and heat absorption
Removable bridge bolt for quick pad change
Will accommodate stock rotors
6 piston, stainless
Common Pad Plate (7420)
Cons:
The Caliper # 120-6585 used in this kit is designated "obsolete" on the Wilwood web site.
I'm not sure what that means, or if there is a current caliper having the same features and can be used in this kit.
Wilwood Forged Narrow Superlight 6R
Brake Kit No: 140-8031
Front only, $1465, pads and 2-piece rotors included
Pros:
Removable Bridgebolt for quick pad change
common Pad plate (7416)
6 Piston, Stainless
Price
Cons:
Does not accommodate stock rotors
Rotor ring replacement cost part # 160-8165, $210 each
16.5mm Pads thicker than stock (14MM) but not as thick as the G-Stop kit ((20mm)
Wilwood SLC56 direct replacement kit
Kit # 140-15173
Front only, $620, with pads, no Rotors
Pros:
Price
Direct fit
Accommodates Stock rotors
Removable Bridgebolt for quick pad change
Common Pad Plate (7416)
Cons:
4 piston
I'm concerned its not a big enough upgrade and I'll be back for bigger/better. (probably easy to sell used though)
AP Racing CP3850/325
Part #: 13.01.10007
Front only: $2600, 2-piece rotors included, No pads
Pros:
4 piston, stainless
Accommodated stock rotors
Common Pad plate (7420)
Accommodates thick 20mm pads
Domed, ventilated SS pistons with anti-knockback springs
High performance rotor design
Con's
A bit more pricey
4 piston (given all the other performance features probably not a real drawback).
Rotor ring replacement, $266 each, shipped (part # CP3908 103GA)
I did not see any kits form Brembo, Alcon, Baer or Stoptech that fit in the 17" wheel. Please attach links to any kits you may find from these other manufacturers.
When you compare the LG kit to the AP racing, if you add a good 2-piece rotor to the LG package, the price is about the same.
Please weigh in on your personal preference and which you think represents the best value for a 3 to 4 HPDE weekender a year, like me.
This is what I have found so far is:
LG G-Stop Wilwood kit.
Front only $1600, Pads included but no rotors. (already mentioned in this thread)
Pros:
20mm pads for long life and heat absorption
Removable bridge bolt for quick pad change
Will accommodate stock rotors
6 piston, stainless
Common Pad Plate (7420)
Cons:
The Caliper # 120-6585 used in this kit is designated "obsolete" on the Wilwood web site.
I'm not sure what that means, or if there is a current caliper having the same features and can be used in this kit.
Wilwood Forged Narrow Superlight 6R
Brake Kit No: 140-8031
Front only, $1465, pads and 2-piece rotors included
Pros:
Removable Bridgebolt for quick pad change
common Pad plate (7416)
6 Piston, Stainless
Price
Cons:
Does not accommodate stock rotors
Rotor ring replacement cost part # 160-8165, $210 each
16.5mm Pads thicker than stock (14MM) but not as thick as the G-Stop kit ((20mm)
Wilwood SLC56 direct replacement kit
Kit # 140-15173
Front only, $620, with pads, no Rotors
Pros:
Price
Direct fit
Accommodates Stock rotors
Removable Bridgebolt for quick pad change
Common Pad Plate (7416)
Cons:
4 piston
I'm concerned its not a big enough upgrade and I'll be back for bigger/better. (probably easy to sell used though)
AP Racing CP3850/325
Part #: 13.01.10007
Front only: $2600, 2-piece rotors included, No pads
Pros:
4 piston, stainless
Accommodated stock rotors
Common Pad plate (7420)
Accommodates thick 20mm pads
Domed, ventilated SS pistons with anti-knockback springs
High performance rotor design
Con's
A bit more pricey
4 piston (given all the other performance features probably not a real drawback).
Rotor ring replacement, $266 each, shipped (part # CP3908 103GA)
I did not see any kits form Brembo, Alcon, Baer or Stoptech that fit in the 17" wheel. Please attach links to any kits you may find from these other manufacturers.
When you compare the LG kit to the AP racing, if you add a good 2-piece rotor to the LG package, the price is about the same.
Please weigh in on your personal preference and which you think represents the best value for a 3 to 4 HPDE weekender a year, like me.
Last edited by Bossdog; 12-09-2016 at 07:50 PM.
12-09-2016, 11:11 PM
#26
Former Vendor
The simple caliper kits, while four pot vs six pot, won't be a significant upgrade. Simply a nicer caliper with easier loading pads. The piston area (like the six in fact) will nearly match that of the stock caliper. In fact all of them do- piston qty is not so important as piston area is really. And keeping things in balance is key.
The FNSL6 kit with 2pc hat and rotor while more money (albeit less than you quoted) will add a bit of valuable rotor mass and improved cooling vs stock. The longevity of the rotor has shown to out last that of the one piece. However in fairness; at 4x the cost nobody will claim 4x the life.
The biggest issue here remains the 17" wheel. None of these kits would be considered ideal by today's standards of larger more robust calipers and 14 to even 15" rotors. You will be forever handicapped by the wheel size. *Part of the reason others don't even address it I suppose is the negative fallout from spending $2500 on something that's not what you wanted it to be?
At the price points of $1300-1500 the options are a value buy. At over $2k you'll wonder what all the hub-bub is about. And for the occasional HPDE user the use of 20mm vs 16mm is about nil. You won't see any added benefit to that. Possibly encountering the need for wheel spacers and longer studs...in fact negating any perceived value.
The KNS/LG Caliper kits and the Wilwood factory FNSL6 kits both offer ample benefit for your need, a price point that's hard to argue with and a host of pad options to run you silly trying out. Ultimately however you'll more than likely shift to the larger wheels and tires in due time I suspect once you've out grown the function of these and the tire options in today's market. Consider them an investment in the learning curve.
The FNSL6 kit with 2pc hat and rotor while more money (albeit less than you quoted) will add a bit of valuable rotor mass and improved cooling vs stock. The longevity of the rotor has shown to out last that of the one piece. However in fairness; at 4x the cost nobody will claim 4x the life.
The biggest issue here remains the 17" wheel. None of these kits would be considered ideal by today's standards of larger more robust calipers and 14 to even 15" rotors. You will be forever handicapped by the wheel size. *Part of the reason others don't even address it I suppose is the negative fallout from spending $2500 on something that's not what you wanted it to be?
At the price points of $1300-1500 the options are a value buy. At over $2k you'll wonder what all the hub-bub is about. And for the occasional HPDE user the use of 20mm vs 16mm is about nil. You won't see any added benefit to that. Possibly encountering the need for wheel spacers and longer studs...in fact negating any perceived value.
The KNS/LG Caliper kits and the Wilwood factory FNSL6 kits both offer ample benefit for your need, a price point that's hard to argue with and a host of pad options to run you silly trying out. Ultimately however you'll more than likely shift to the larger wheels and tires in due time I suspect once you've out grown the function of these and the tire options in today's market. Consider them an investment in the learning curve.
The following users liked this post:
Sam Handwich (12-10-2016)
12-10-2016, 12:22 PM
#27
Burning Brakes
The simple caliper kits, while four pot vs six pot, won't be a significant upgrade. Simply a nicer caliper with easier loading pads. The piston area (like the six in fact) will nearly match that of the stock caliper. In fact all of them do- piston qty is not so important as piston area is really.
12-10-2016, 03:13 PM
#28
Former Vendor
But isn't there a bit of pad leverage improvement with more pistons? Example: a single piston per side will provide more pressure against the center of the pad than the ends, but 3 pistons per side will provide more even pressure along the length of the pad. Maybe it's not a big deal.
For the most part no. Assuming you look behind the pad:
1 piston of say 2.25"
2 pistons of 1.625"
3 pistons of staggered size 1.125, 1.125, 1.625"
All are about 4" of area. Meaning the do the same thing with regard to clamp force.
Under high pressure the single piston can deflect the pad plate some. The two pot some tapering. The three pot spreading it out more.
Overall the qty change to pistons has nothing to do with force. It's just to allow for both a bigger caliper body and pad. Think about it: if the pads is now 6" long inside a 13" caliper body it would be terribly inefficient with one big piston.
While more area does equate to more clamping it's only relative to the input line pressure. And deviating from the factory spec will mess up the cars balance and pedal feel.
Longer (viewed taller) pads DO bump up the radius of the pad a bit also. That aspect applies the same pressure (area) to a higher spot on the rotor. To that extent yes a pad with more pistons would have an advantage as it's average pressure point is out farther from center. That value is not huge usually...can be on some real short squatty pads but not so much on the Vette as they are already more narrow.
Last edited by Todd TCE; 12-10-2016 at 03:16 PM.
12-10-2016, 10:10 PM
#29
Racer
The simple caliper kits, while four pot vs six pot, won't be a significant upgrade. Simply a nicer caliper with easier loading pads. The piston area (like the six in fact) will nearly match that of the stock caliper. In fact all of them do- piston qty is not so important as piston area is really. And keeping things in balance is key.
The FNSL6 kit with 2pc hat and rotor while more money (albeit less than you quoted) will add a bit of valuable rotor mass and improved cooling vs stock. The longevity of the rotor has shown to out last that of the one piece. However in fairness; at 4x the cost nobody will claim 4x the life.
The biggest issue here remains the 17" wheel. None of these kits would be considered ideal by today's standards of larger more robust calipers and 14 to even 15" rotors. You will be forever handicapped by the wheel size. *Part of the reason others don't even address it I suppose is the negative fallout from spending $2500 on something that's not what you wanted it to be?
At the price points of $1300-1500 the options are a value buy. At over $2k you'll wonder what all the hub-bub is about. And for the occasional HPDE user the use of 20mm vs 16mm is about nil. You won't see any added benefit to that. Possibly encountering the need for wheel spacers and longer studs...in fact negating any perceived value.
The KNS/LG Caliper kits and the Wilwood factory FNSL6 kits both offer ample benefit for your need, a price point that's hard to argue with and a host of pad options to run you silly trying out. Ultimately however you'll more than likely shift to the larger wheels and tires in due time I suspect once you've out grown the function of these and the tire options in today's market. Consider them an investment in the learning curve.
The FNSL6 kit with 2pc hat and rotor while more money (albeit less than you quoted) will add a bit of valuable rotor mass and improved cooling vs stock. The longevity of the rotor has shown to out last that of the one piece. However in fairness; at 4x the cost nobody will claim 4x the life.
The biggest issue here remains the 17" wheel. None of these kits would be considered ideal by today's standards of larger more robust calipers and 14 to even 15" rotors. You will be forever handicapped by the wheel size. *Part of the reason others don't even address it I suppose is the negative fallout from spending $2500 on something that's not what you wanted it to be?
At the price points of $1300-1500 the options are a value buy. At over $2k you'll wonder what all the hub-bub is about. And for the occasional HPDE user the use of 20mm vs 16mm is about nil. You won't see any added benefit to that. Possibly encountering the need for wheel spacers and longer studs...in fact negating any perceived value.
The KNS/LG Caliper kits and the Wilwood factory FNSL6 kits both offer ample benefit for your need, a price point that's hard to argue with and a host of pad options to run you silly trying out. Ultimately however you'll more than likely shift to the larger wheels and tires in due time I suspect once you've out grown the function of these and the tire options in today's market. Consider them an investment in the learning curve.
12-11-2016, 01:40 PM
#30
Former Vendor
It's not my intent to sway you on the wheels..but I feel obligated to point out that the kits we are speaking of (while fine products and all) were the root of things most folks out grew in time. For you it's a slight 'upgrade' from oe now perhaps yes.
I do feel that if you're going to shell out $1500-2500 for the brakes that you'd be better served in doing so with larger more robust parts. And doing it one time. None of the kits working with 17s will have a simple parts swap allowing you to bump up 1" in rotor size- the calipers won't fit that spec.
I do feel that if you're going to shell out $1500-2500 for the brakes that you'd be better served in doing so with larger more robust parts. And doing it one time. None of the kits working with 17s will have a simple parts swap allowing you to bump up 1" in rotor size- the calipers won't fit that spec.
12-12-2016, 09:53 PM
#31
Racer
It's not my intent to sway you on the wheels..but I feel obligated to point out that the kits we are speaking of (while fine products and all) were the root of things most folks out grew in time. For you it's a slight 'upgrade' from oe now perhaps yes.
I do feel that if you're going to shell out $1500-2500 for the brakes that you'd be better served in doing so with larger more robust parts. And doing it one time. None of the kits working with 17s will have a simple parts swap allowing you to bump up 1" in rotor size- the calipers won't fit that spec.
I do feel that if you're going to shell out $1500-2500 for the brakes that you'd be better served in doing so with larger more robust parts. And doing it one time. None of the kits working with 17s will have a simple parts swap allowing you to bump up 1" in rotor size- the calipers won't fit that spec.
If I ran 275/35/18 on the front and 305/35/18 on the rear, that maintains the .97 tire circumference ratio but kills the "square" setup
I don't have a feel how much braking improvement the 14" rotor delivers over the 13". Additional heat dissipation, but will most realize that in a 20 to 25 min HPDE session? I'm not a "throw-out-the-anchor" late braker.
Last edited by Bossdog; 12-12-2016 at 09:54 PM.
12-13-2016, 09:44 AM
#32
Former Vendor
One of the concerns I have going to 18's in the front is the Stability control system.
I don't have a feel how much braking improvement the 14" rotor delivers over the 13". Additional heat dissipation, but will most realize that in a 20 to 25 min HPDE session? I'm not a "throw-out-the-anchor" late braker.
I don't have a feel how much braking improvement the 14" rotor delivers over the 13". Additional heat dissipation, but will most realize that in a 20 to 25 min HPDE session? I'm not a "throw-out-the-anchor" late braker.
You won't see so much "braking improvement" - if by that you're expecting shorter stopping distances. Total brake torque will be maximum tire adhesion. With the bigger rotors you will use more leverage rather than more clamp force. A bit less line pressure and stress on the calipers.
The rear change is the thermal management. The goal is of course equal stopping on the 15th lap as it is on the 1st lap. More rotor mass is key to cycling the ups and downs of rotor temps. Heat saturation becomes much more of a problem on a smaller disc of course.
