Fact or Fiction: Drilled/Slotted rotors improve braking
#1
Melting Slicks
Thread Starter
Fact or Fiction: Drilled/Slotted rotors improve braking
This should be an interesting thread since so many Corvette owners feel that drilled/slotted rotors are just "Bling-Bling". As the title says, state your position and back it up with any facts available.
#2
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St. Jude Donor '05-'06-'07-'08-'09, '14-'15-'16-'17-'18
Originally Posted by Vettlldo
This should be an interesting thread since so many Corvette owners feel that drilled/slotted rotors are just "Bling-Bling". As the title says, state your position and back it up with any facts available.
#3
Safety Car
The idea of drilled rotors was intended to increase cooling. It probably does on rotors that are designed for this. StopFORCE rotors are the only rotors that have demonstrated the holes are useful. Also, the drilled holes cause the rotors to crack around them from heavy braking. Lots of force. The slots are designed to help 'outgassing' or hot gasses that build up between the rotor and the pad to escape.
I agree with Red Racer that it's bling bling, but I just bought a set of AC Delco slotted and drilled rotors. They look sooooo nice on my buddies car.
I agree with Red Racer that it's bling bling, but I just bought a set of AC Delco slotted and drilled rotors. They look sooooo nice on my buddies car.
#4
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Heh, I thought the holes were to help with outgassing, and the slots were to wipe the pad. Any sharp edge on the rotor creates a stress riser. The inside edge of drilled holes are sharp, thus they are stress risers. For facts about stress risers, read some of the books in the C5 General Sticky, Mark's Handbook for Mechanical Engineers, or just do a search instead of asking other people to do it for you. You're asking a newbie question, so please educate yourself with some heavy search feature action, and then come back and ask more questions.
#5
Melting Slicks
Thread Starter
Originally Posted by leaftye
Heh, I thought the holes were to help with outgassing, and the slots were to wipe the pad. Any sharp edge on the rotor creates a stress riser. The inside edge of drilled holes are sharp, thus they are stress risers. For facts about stress risers, read some of the books in the C5 General Sticky, Mark's Handbook for Mechanical Engineers, or just do a search instead of asking other people to do it for you. You're asking a newbie question, so please educate yourself with some heavy search feature action, and then come back and ask more questions.
#6
Team Owner
No one I know here races with them. New pads don't need out gassing. We are convinced, now you can do research if you like. Try all the major race brake vendors. Some AP's have small hook like cuts about 1/2" in the rotors but they have sponsors and don't worry about cheese graters or cost. Go to a AMLS race and see what is in the pits.
Bling Bling
Bling Bling
#7
Team Owner
If you are heating up your rotors to the maximum allowed temps in a racing situation, slotted would be your best bet. If you are pushing it hard but not to where too much heat is a problem a solid rotor would be good. If you just drive your car around very carefully and want it to look pretty, then get the slotted, cross drilled and zinc washed rotors. Hell, might as well get them gold plated...
VR
VR
#9
Le Mans Master
THere are probably some MINOR benefits to slotted/cross drilled rotors, but not near enough to make up for their main disadvantage of not being able to take the heat as well as a solid rotor can. If you are not on a road course, there is no way to heat them up enough for it to matter. Most of the improvement that people think they feel when they get new rotors is from fresh brake fluid, not the rotors
#10
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Here we go again
and this one is after only 4 HOURS of track use on Porsche GT3 cup car
And in the Pits of a Grand-Am race
Caddy CTSv
AP racing on the SunTrust car
Performance Friction Brakes
and the C5R
Now where were those drilled rotors???
and this one is after only 4 HOURS of track use on Porsche GT3 cup car
And in the Pits of a Grand-Am race
Caddy CTSv
AP racing on the SunTrust car
Performance Friction Brakes
and the C5R
Now where were those drilled rotors???
Last edited by AU N EGL; 02-25-2005 at 08:04 AM.
#11
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From the Stoptech web site: http://www.stoptech.com/faq/
From Wilwood: http://www.wilwood.com/Centers/Infor....asp#question7
Which is better, slotted or drilled rotors?
StopTech provides rotors slotted, drilled or plain. For most performance applications slotted is the preferred choice. Slotting helps wipe away debris from between the pad and rotor as well as increasing the "bite" characteristics of the pad. A drilled rotor provides the same type of benefit, but is more susceptible to cracking under severe usage. Many customers prefer the look of a drilled rotor and for street and occasional light duty track use they will work fine. For more severe applications, we recommend slotted rotors.
StopTech provides rotors slotted, drilled or plain. For most performance applications slotted is the preferred choice. Slotting helps wipe away debris from between the pad and rotor as well as increasing the "bite" characteristics of the pad. A drilled rotor provides the same type of benefit, but is more susceptible to cracking under severe usage. Many customers prefer the look of a drilled rotor and for street and occasional light duty track use they will work fine. For more severe applications, we recommend slotted rotors.
Q: Why are some rotors drilled or slotted?
A: Rotors are drilled to reduce rotating weight, an issue near and dear to racers searching for ways to minimize unsprung weight. Drilling diminishes a rotor's durability and cooling capacity.
Slots or grooves in rotor faces are partly a carryover from the days of asbestos pads. Asbestos and other organic pads were prone to "glazing" and the slots tended to help "scrape or de-glaze" them. Drilling and slotting rotors has become popular in street applications for their pure aesthetic value. Wilwood has a large selection of drilled and slotted rotors for a wide range of applications.
A: Rotors are drilled to reduce rotating weight, an issue near and dear to racers searching for ways to minimize unsprung weight. Drilling diminishes a rotor's durability and cooling capacity.
Slots or grooves in rotor faces are partly a carryover from the days of asbestos pads. Asbestos and other organic pads were prone to "glazing" and the slots tended to help "scrape or de-glaze" them. Drilling and slotting rotors has become popular in street applications for their pure aesthetic value. Wilwood has a large selection of drilled and slotted rotors for a wide range of applications.
#12
Burning Brakes
Make it simple:
FICTION
Cross-drilling:
They where created to allow gas from the pads, out-gassing, to escape so it does not create a barrier.
They where never meant to be used for long, one race and in the garbage.
No modern pad out-gasses anymore until the temperature gets so high that the brake fluid stops being fluid and goes into a gaseous state.
Now the "hype" is that they improve cooling. And on a brake dyno test stand or in simulations they do somewhat. The theory being that air is drawn through the holes and out the vents.
In the real world, they don't because the air flow is way too turbulent. You turn the wheel, the car moves up and down, sideways, etc., etc.
It's old technology for an old problem.
Slotted:
Where also created for out-gassing, actually slotted rotors where invented because drilled rotors cracked so badly and so often.
Slotted rotors do have a slight benefit in the real world of "pad cleaning" which is basically scraping a very thin film off the pad. It actually does happen, but it probably has no effect on braking distances. And not worth any extra cost. For an out and out race car it's probably worth it because they can use every little 1/1000 of a second.
Slotted rotors will increase pad wear noticeably.
Damn - Au is fast
FICTION
Cross-drilling:
They where created to allow gas from the pads, out-gassing, to escape so it does not create a barrier.
They where never meant to be used for long, one race and in the garbage.
No modern pad out-gasses anymore until the temperature gets so high that the brake fluid stops being fluid and goes into a gaseous state.
Now the "hype" is that they improve cooling. And on a brake dyno test stand or in simulations they do somewhat. The theory being that air is drawn through the holes and out the vents.
In the real world, they don't because the air flow is way too turbulent. You turn the wheel, the car moves up and down, sideways, etc., etc.
It's old technology for an old problem.
Slotted:
Where also created for out-gassing, actually slotted rotors where invented because drilled rotors cracked so badly and so often.
Slotted rotors do have a slight benefit in the real world of "pad cleaning" which is basically scraping a very thin film off the pad. It actually does happen, but it probably has no effect on braking distances. And not worth any extra cost. For an out and out race car it's probably worth it because they can use every little 1/1000 of a second.
Slotted rotors will increase pad wear noticeably.
Damn - Au is fast
Last edited by Mighty-Mouse; 02-25-2005 at 04:34 PM.
#13
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Originally Posted by Mighty-Mouse
Make it simple:
FICTION
Damn - Au is fast
FICTION
Damn - Au is fast
#14
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Originally Posted by Vettlldo
Don't get your panties in a bunch and don't think for a minute you can get away with intimidating people in a public forum. Do your own searches in this forum and you will find that all threads on drilled/slotted rotors are just opinions and not based on facts.
You discounted all the posts by the forum members when you said "all threads on drilled/slotted rotors are just opinions" and almost all the information in this thread is from this forum. You do realize this is also a drilled/slotted rotor thread don't you?? I gave you good information, and solid offline references, but if that's not good enough for you, you're not just a newbie, you're a hopeless newbie.
#15
Team Owner
FWIW, this is what I am running.. 13.60" 2 piece SOLID rotors, 6 piston fronts, 4 piston rears, 2 diff kinds of compounds for street and track. I purchased 2 new sets of custom built wheels (one for street, one for track) to fit over the monster calipers... serious brakes are no joke, not cheap but will work much better than OE systems.
VR
VR
#16
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Originally Posted by vetterdstr
If you are heating up your rotors to the maximum allowed temps in a racing situation, slotted would be your best bet. If you are pushing it hard but not to where too much heat is a problem a solid rotor would be good. If you just drive your car around very carefully and want it to look pretty, then get the slotted, cross drilled and zinc washed rotors. Hell, might as well get them gold plated...
VR
VR
#17
Drifting
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Good responses, I believe the C5R team utilize a slotted rotor for gas venting, not for cooling or added stopping power. As for mechanical application, more surface contact, more friction, more ft-lbs pressure, better braking force = less travel.
So who cares, drilled rotors do look good, but I will stay with my solids. In a wet emergancy situation your life is better than mod looks.
So who cares, drilled rotors do look good, but I will stay with my solids. In a wet emergancy situation your life is better than mod looks.
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As stated cross drilled are pretty but not good
Slotted are better but still a waste Both is stupid, you are loosing surface, and you have a weak rotor, not the best option.
Slotted are better but still a waste Both is stupid, you are loosing surface, and you have a weak rotor, not the best option.
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Originally Posted by yellow01
...and I bet they stop like mad...