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I'm a little confused. With the the praise and comparison of the Jaguar F Type to the Porsche Cayman and 911.
My question is the brakes. The Cayman and 911 have cross drilled rotors with 4 piston fixed calipers front and rear.
The is the best brake setup that exists.
The F Type does not have cross drilled rotors and it has sliding calipers.
Sliding calipers are cheaper and lighter to manufacture.
Almost all cars regardless of price have sliding calipers.
Fixed calipers is the rarity today.
Fixed calipers are for vehicles that can achieve very high speed or heavy vehicles with a reasonable amount of speed.
Fixed calipers are able to produce more braking pressure on the disks and stop the vehicle faster and in a straighter line than sliding calipers.
Is Jaguar cutting corners on this car that produces 550hp by using sliding calipers?
Isn't today's standard for vehicles such as these fixed calipers?
 

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I think you'd have to drive the car and see if it stops adequately enough for you. What about not having brakes at the wheels at all but rather having them inboard on the axle? Jaguar did that years ago and some people swear by them still. I don't think it really much matters in the modern age what flavor of caliper you use as long as it is up to the task and doesn't cause the brakes to feel funny. I did not have any issue with the brakes in the F-Type that I drove so they could have been made of turboencabulator nano-plastic resins and I wouldn't have cared. :)

I'd say drive and see for yourself.
 

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My wife's F-Type will dislodge eyeballs from their sockets if traction is good. Same with my Porsche. Cooling and tires are the limiting factors outside of F1, etc.

As far as cross-drilled rotors; they are just for looks. I wouldn't have them if I'd had a choice. (from the factory ... I know I can replace them!) They wear poorly and are more prone to cracking. Long gone are the days of brake pads that off-gas enough to need ventilation.
 

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I think you'd have to drive the car and see if it stops adequately enough for you. What about not having brakes at the wheels at all but rather having them inboard on the axle? Jaguar did that years ago and some people swear by them still. I don't think it really much matters in the modern age what flavor of caliper you use as long as it is up to the task and doesn't cause the brakes to feel funny. I did not have any issue with the brakes in the F-Type that I drove so they could have been made of turboencabulator nano-plastic resins and I wouldn't have cared. :)

I'd say drive and see for yourself.
My 1972 Audi 100LS had inboard disk brakes. The car rode and handled well compared to Anerican sedans of its day, but what a pain it was to replace the pads!
 

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You could say they are cutting corners, or maybe the brakes just worked for them?

Even BMW has been using floating calipers for their M3 in the E92 generation. No biggie really. But yes, generally speaking fixed calipers are more desirable due to:

1. they look nicer
2. they look nicer
3. generally firmer pedal feel (arguable ... as our pedals aren't the best out there)
4. better heat dissipation if designed well (which is actually a weakness on M3s)
5. greater clamping force (although braking power nowadays are usually less constrained by this)
6. they look nicer
7. they look nicer
8. they look nicer
9. they look nicer
10. Did I forget to say ... they look nicer?
 

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You could say they are cutting corners, or maybe the brakes just worked for them?

Even BMW has been using floating calipers for their M3 in the E92 generation. No biggie really. But yes, generally speaking fixed calipers are more desirable due to:

1. they look nicer
2. they look nicer
3. generally firmer pedal feel (arguable ... as our pedals aren't the best out there)
4. better heat dissipation if designed well (which is actually a weakness on M3s)
5. greater clamping force (although braking power nowadays are usually less constrained by this)
6. they look nicer
7. they look nicer
8. they look nicer
9. they look nicer
10. Did I forget to say ... they look nicer?

But...How do they look?!?
 

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I talked to an indie shop and they said that rotors with wholes are pointless and for looks than anything else. Worse, the holes can cause fractures and break in the winter and salty wet conditions.

brakes are brakes. Bigger rotor and pad and you'll stop faster. People usually care about pedal feel more.
 

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Floating Caliper on BMW

BFront05NewRotorCaliper.jpg



Fixed Caliper on Porsche

pfcrotor.jpg


The whole slotted vs slotted+drilled vs drilled vs plain discs is another whole big discussion. In summary, my take is slotted ones are my preferred ones.
 

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The whole slotted vs slotted+drilled vs drilled vs plain discs is another whole big discussion. In summary, my take is slotted ones are my preferred ones.
Ditto. I've had many a drilled disc crack across the holes but no issues at all with grooved.
 

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Maybe a nit being picked but if memory serves, the Porsche are cast not cross drilled with holes. Cross drilling is more likely to crack than holes cast in as drilling creates stress in the metal immediately surrounding the holes (engineers may want to weigh in and keep me honest here)............and the holes do facilitate gas dissipation working with the ventilation within the rotor itself.
 

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My wife's F-Type will dislodge eyeballs from their sockets if traction is good. Same with my Porsche. Cooling and tires are the limiting factors outside of F1, etc.

As far as cross-drilled rotors; they are just for looks. I wouldn't have them if I'd had a choice. (from the factory ... I know I can replace them!) They wear poorly and are more prone to cracking. Long gone are the days of brake pads that off-gas enough to need ventilation.
Actually there are several advantages of drilled rotors. The first is heat. When the brake pad grabs the rotor, it creates friction, which creates heat. If that heat can't escape, it leads to brake fade, which reduces the brakes' stopping power. The second reason is that it reduces gas build up which can reduce stopping power. The last reason is water. If a car drives through a puddle, a carwash or even a rainstorm, the brake rotors can get wet. A wet brake rotor is slippery and difficult for the brake pads to grab. Having drilled holes on a brake rotor makes it easy for heat, gas and water to be quickly moved away from the rotor surface, keeping the brake performance strong.

I do agree that the cross drilling weakens the rotor and could cause fractures, but this would only be an issue for someone who regularly tracks his car in which case I would recommend slotted rotors which have all of the advantages of a drilled rotor but are far more durable.
 

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... brakes are brakes. Bigger rotor and pad and you'll stop faster.
Bigger rotors and/or pads may increase fade resistance after repeated or prolonged braking, but the limiting factor for braking most modern high performance cars is tire adhesion, not swept area.
 

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Bigger rotors and/or pads may increase fade resistance after repeated or prolonged braking, but the limiting factor for braking most modern high performance cars is tire adhesion, not swept area.
I believe this, but I've heard that swept area also matters and that bigger brakes work better. I also believe that a rearward weight bias helps because you get more even weight distribution under braking. I suspect a stiffer front suspension also helps because the car spends less time diving and builds weight on the front tires faster when one suddenly brakes, as in a panic stop. From what I've read, tires (and road conditions) are king, but theses others are not insignificant.
 

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Maybe a nit being picked but if memory serves, the Porsche are cast not cross drilled with holes. Cross drilling is more likely to crack than holes cast in as drilling creates stress in the metal immediately surrounding the holes (engineers may want to weigh in and keep me honest here)............and the holes do facilitate gas dissipation working with the ventilation within the rotor itself.
Yes and no. All discs are casted in beginning and then drilled after. The cost of the discs would be grossly higher if the holes were casted in the beginning. our OEM discs still crack under heavy track use if you run a search on the forum. These are quality OEM discs, but definitely has its flaws.

Anyway, the point of slotted and drilled rotors is for gas to escape etc. However, nowadays the pads are good enough that slotted would do the job. Porsche claims the drilled holes will help under wet conditions, but I wonder how much that is really worth in reality. Truth is, drilled rotors look "cooler" and for practical purposes ... drilled rotors will make the car sell better :D
 

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The biggest advantage of fixed calipers is when you can change the pads without removing the caliper. For some reason they decided not to allow that with my 981's front brakes. Now I have to get around to removing the calipers to see what's what.
 

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Ferraris and others have drilled rotors. Surely they all can't be doing it just for looks...

Maybe?
 
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