Brake rotors
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From: German Ambassador, Hessen
Brake rotors
Hey there,
I searched Ebay for ITR aftermarket brake rotors and found this:
"Brembo OE "blank" rotors offer better performance than Cross-drilled rotors. Cross-drilled rotors might look "cool", but what are they really doing for performance? Brake rotors were first "drilled" in the 40's and 50's because early brake pad materials gave off gasses when heated to racing temperatures, which is called "gassing out". These gasses then formed a thin layer between the brake pad face and the rotor, effectively lowering the coefficient of friction. The "cross drilled" holes were implemented to give the gasses a place to escape. Today’s brake pad materials do not exhibit the same gassing out problems as these early (old) pads. Also, there are many companies that sell "cheap" cross-drilled and slotted rotors. They do this by purchasing Brembo blanks and having them cheaply altered by a third party. Doing this sacrifices the rotors structural integrity, and can be a huge safety risk. If you contact Brembo, they will not recognize these discs after they have been altered. These rotors are known to crack and warp very quickly. If you want the actual Brembo cross drilled and slotted rotors you will be paying much more. That's why these blanks are perfect; they perform better, do not tear through pads, are priced much lower, and are much safer.
"
So I searched Honda Tech and found this thread:
https://honda-tech.com/zerothread?id=585923
Unfortunatly, the link the guy "nosepkr" posted doesn`t function anymore. Who of you has detailed knowledge about blank/drilled rotors and how they work in the year 2004 ?
I searched Ebay for ITR aftermarket brake rotors and found this:
"Brembo OE "blank" rotors offer better performance than Cross-drilled rotors. Cross-drilled rotors might look "cool", but what are they really doing for performance? Brake rotors were first "drilled" in the 40's and 50's because early brake pad materials gave off gasses when heated to racing temperatures, which is called "gassing out". These gasses then formed a thin layer between the brake pad face and the rotor, effectively lowering the coefficient of friction. The "cross drilled" holes were implemented to give the gasses a place to escape. Today’s brake pad materials do not exhibit the same gassing out problems as these early (old) pads. Also, there are many companies that sell "cheap" cross-drilled and slotted rotors. They do this by purchasing Brembo blanks and having them cheaply altered by a third party. Doing this sacrifices the rotors structural integrity, and can be a huge safety risk. If you contact Brembo, they will not recognize these discs after they have been altered. These rotors are known to crack and warp very quickly. If you want the actual Brembo cross drilled and slotted rotors you will be paying much more. That's why these blanks are perfect; they perform better, do not tear through pads, are priced much lower, and are much safer.
"
So I searched Honda Tech and found this thread:
https://honda-tech.com/zerothread?id=585923
Unfortunatly, the link the guy "nosepkr" posted doesn`t function anymore. Who of you has detailed knowledge about blank/drilled rotors and how they work in the year 2004 ?
FSAE
Joined: Jan 2002
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From: Drinking Beer, UT
Re: Brake rotors (ITR5874)
That info is very much true.
Slottled rotors offer better cooling, while drilled offer gas exchange. Most pads on the market are metallic based now, and do not need such a huge area for escaping gasses.
For every STREET application, a blank surfaced rotor will perform better than any slotted or cross drilled one of the same diameter, or even slightly larger.
You will see 50x more braking improvement from good pads and solid rotors than you would by purchasing 'show kaa rotors'.
Most people on this board use OE blanks, whether actual Honda peices, or from Autozone or Brembo. I personally use Cobalt Friction rotors on my car, and although no real braking improvement was noticed, they sure do last longer than Autozone and OE rotors.
Slottled rotors offer better cooling, while drilled offer gas exchange. Most pads on the market are metallic based now, and do not need such a huge area for escaping gasses.
For every STREET application, a blank surfaced rotor will perform better than any slotted or cross drilled one of the same diameter, or even slightly larger.
You will see 50x more braking improvement from good pads and solid rotors than you would by purchasing 'show kaa rotors'.
Most people on this board use OE blanks, whether actual Honda peices, or from Autozone or Brembo. I personally use Cobalt Friction rotors on my car, and although no real braking improvement was noticed, they sure do last longer than Autozone and OE rotors.
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From: Charlotte
Re: Brake rotors (ITR5874)
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From: RIP Craig Jones
Re: Brake rotors (92TypeR)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92TypeR »</TD></TR><TR><TD CLASS="quote">Slottled rotors offer better cooling</TD></TR></TABLE>
Horseshit.
Horseshit.
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From: Hollywood Babylon
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From: German Ambassador, Hessen
Trending Topics
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From: German Ambassador, Hessen
Re: Brake rotors (.RJ)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ »</TD></TR><TR><TD CLASS="quote">
Horseshit.</TD></TR></TABLE>
Please explain.
Horseshit.</TD></TR></TABLE>
Please explain.
FSAE
Joined: Jan 2002
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From: Drinking Beer, UT
Re: Brake rotors (ITR5874)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITR5874 »</TD></TR><TR><TD CLASS="quote">
Please explain. </TD></TR></TABLE>
Yes please do.
I understand well that they have minimal to no effect on a street or even light duty track car, but for heavier cars, and hard track driving, having a *few* slots in your rotor will help cool your pads. I know our 3700lb supra sure does have less brake fade with our slotted rotors compared to before, and that is the only difference.
Yes there are more effective ways to get better cooling...ie: ducting, thicker vented rotors...but having slotted rotors does have an effect on heat dissipation.
Please explain. </TD></TR></TABLE>
Yes please do.
I understand well that they have minimal to no effect on a street or even light duty track car, but for heavier cars, and hard track driving, having a *few* slots in your rotor will help cool your pads. I know our 3700lb supra sure does have less brake fade with our slotted rotors compared to before, and that is the only difference.
Yes there are more effective ways to get better cooling...ie: ducting, thicker vented rotors...but having slotted rotors does have an effect on heat dissipation.
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From: RIP Craig Jones
Re: Brake rotors (ITR5874)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITR5874 »</TD></TR><TR><TD CLASS="quote">Please explain. </TD></TR></TABLE>
Convection.
Convection.
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From: IL
Re: Brake rotors (92TypeR)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92TypeR »</TD></TR><TR><TD CLASS="quote">I understand well that they have minimal to no effect on a street or even light duty track car, but for heavier cars, and hard track driving, having a *few* slots in your rotor will help cool your pads. I know our 3700lb supra sure does have less brake fade with our slotted rotors compared to before, and that is the only difference.
Yes there are more effective ways to get better cooling...ie: ducting, thicker vented rotors...but having slotted rotors does have an effect on heat dissipation.</TD></TR></TABLE>
Slots have nothing to do with cooling. Their primary purposes are to let gas out and to revive friction surface everytime you hit the brakes. (OT: I would imagine that slotted rotors would have no problem with glazed pads, as the slots would scrap down the glazed surface anyway.)
Cross-drill, on the other hand, provides higher air flow and would benefit cooling even though the metal volume is less. But vanes and holes require careful engineering and design, or it would not ventilate how it's supposed to be and to make it worse, you would have less metal volume to absorb heat.
It also does not make sense to buy rotors that are drilled or slotted afterwards. During the drilling and slotting process, internal stress would be created and when the rotors experience high heat, it would crack right along the stress concentration points.
People always bring up the argument of, "then how come all the high end sports or race cars use cross-drilled and slotted rotors?" It's because the holes and slots on those rotors are cast in place, and the vanes and holes are carefully engineered to work with each other. It also means that they are much more expensive to make. Just an example, a set of AP slotted rotors, just the replacement discs, not including the hub, cost about $500USD. Porsche or Ferrari racers can afford that no problem.
For us ITR owners, the best we could do is probably the StopTech or Zeal 2-piece slotted rotors. But they still cost $400+USD.
Yes there are more effective ways to get better cooling...ie: ducting, thicker vented rotors...but having slotted rotors does have an effect on heat dissipation.</TD></TR></TABLE>
Slots have nothing to do with cooling. Their primary purposes are to let gas out and to revive friction surface everytime you hit the brakes. (OT: I would imagine that slotted rotors would have no problem with glazed pads, as the slots would scrap down the glazed surface anyway.)
Cross-drill, on the other hand, provides higher air flow and would benefit cooling even though the metal volume is less. But vanes and holes require careful engineering and design, or it would not ventilate how it's supposed to be and to make it worse, you would have less metal volume to absorb heat.
It also does not make sense to buy rotors that are drilled or slotted afterwards. During the drilling and slotting process, internal stress would be created and when the rotors experience high heat, it would crack right along the stress concentration points.
People always bring up the argument of, "then how come all the high end sports or race cars use cross-drilled and slotted rotors?" It's because the holes and slots on those rotors are cast in place, and the vanes and holes are carefully engineered to work with each other. It also means that they are much more expensive to make. Just an example, a set of AP slotted rotors, just the replacement discs, not including the hub, cost about $500USD. Porsche or Ferrari racers can afford that no problem.
For us ITR owners, the best we could do is probably the StopTech or Zeal 2-piece slotted rotors. But they still cost $400+USD.
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From: kuidaore
Re: Brake rotors (Wai)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Wai »</TD></TR><TR><TD CLASS="quote">
People always bring up the argument of, "then how come all the high end sports or race cars use cross-drilled and slotted rotors?" It's because the holes and slots on those rotors are cast in place, and the vanes and holes are carefully engineered to work with each other. It also means that they are much more expensive to make. Just an example, a set of AP slotted rotors, just the replacement discs, not including the hub, cost about $500USD. Porsche or Ferrari racers can afford that no problem.
</TD></TR></TABLE>
Just Devil's Advocate I guess, but from what we've previously discussed in the RRAX forum on the topic of Cast or Drilled Holes on Rotors, from what I understand, Noone "Casts" Holes in Rotors. This Included the likes of Brembo and or for Porsche Engineering.
Like I mentioned over there in a recent post I clearly remember in the recent past (but unfortunately misplaced the link) to a Porsche forum where a brake engineer from Brembo clearly stated that neither Brembo or any other brake manufacturer that he knew of casts holes in rotors. They are All drilled. The complication of the process (including cost) and inconsistancy in molecular structure prohibits this type of manufacturing process for brake rotors.
Damn, I really need to find that link again...
As you were.
Sorry if I added nothing constructive.
People always bring up the argument of, "then how come all the high end sports or race cars use cross-drilled and slotted rotors?" It's because the holes and slots on those rotors are cast in place, and the vanes and holes are carefully engineered to work with each other. It also means that they are much more expensive to make. Just an example, a set of AP slotted rotors, just the replacement discs, not including the hub, cost about $500USD. Porsche or Ferrari racers can afford that no problem.
</TD></TR></TABLE>
Just Devil's Advocate I guess, but from what we've previously discussed in the RRAX forum on the topic of Cast or Drilled Holes on Rotors, from what I understand, Noone "Casts" Holes in Rotors. This Included the likes of Brembo and or for Porsche Engineering.
Like I mentioned over there in a recent post I clearly remember in the recent past (but unfortunately misplaced the link) to a Porsche forum where a brake engineer from Brembo clearly stated that neither Brembo or any other brake manufacturer that he knew of casts holes in rotors. They are All drilled. The complication of the process (including cost) and inconsistancy in molecular structure prohibits this type of manufacturing process for brake rotors.
Damn, I really need to find that link again...
As you were.
Sorry if I added nothing constructive.
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From: IL
You maybe right.
But I did read an article on the maufacturing process of the Porsche carbon brake discs. It shows how the pile of metal powder tranform into a disc. It also shows the cast split in half, with all the bumps where the holes are supposed to be.
But I did read an article on the maufacturing process of the Porsche carbon brake discs. It shows how the pile of metal powder tranform into a disc. It also shows the cast split in half, with all the bumps where the holes are supposed to be.
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From: RIP Craig Jones
Re: (Wai)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Wai »</TD></TR><TR><TD CLASS="quote">with all the bumps where the holes are supposed to be.</TD></TR></TABLE>
In this case, then both are true...
The holes then would be an additional machining process, but the casting process would be done so that stress risers are not created when the holes are drilled.
Nearly impossible to cast (or form, in the case of powdered metal) the disc with the finished holes in place cost-effectively.
In this case, then both are true...
The holes then would be an additional machining process, but the casting process would be done so that stress risers are not created when the holes are drilled.
Nearly impossible to cast (or form, in the case of powdered metal) the disc with the finished holes in place cost-effectively.
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From: kuidaore
Re: (Wai)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Wai »</TD></TR><TR><TD CLASS="quote">You maybe right.
But I did read an article on the maufacturing process of the Porsche carbon brake discs. It shows how the pile of metal powder tranform into a disc. It also shows the cast split in half, with all the bumps where the holes are supposed to be.</TD></TR></TABLE>
Ha Ha!
I finally Fuggin found the link!!!
https://honda-tech.com/zerothread?id=655608
And where I remembered this discussion from:
http://corner-carvers.com/foru...ber=1
And what John says: "Pay attention to SilverSnake's posts in this thread on CornerCarver. On the top of Page 2:"
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Silversnake »</TD></TR><TR><TD CLASS="quote">"However, one intersting item is that all of our X-drilled holes are exactly that....drilled.....even the Porsche ones. Its a bit of an urban legend that Porsche "casts-in their holes" for strength. Truth is, when I started with Brembo I thought the same thing. I mentioned it to our Italian resident Applications Engineer. I was kinda surprised myself. He laughed and added, "People seriously think we cast in all of the holes? Wow, I'd love to see the mold for that! No, actually they are all drilled and chamfered post-casting. "</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Silversnake »</TD></TR><TR><TD CLASS="quote">My personal opinion is with today's materials its mostly for bling. there are some slight benifits to it, but there are also some negatives. There have been Brembo/Porsche tests to show that x-drilled rotors increases first effectiveness in wet conditions. Assuming there is enough mass for thermal capacity of the application, X-drilling can save a slight amount of weight (although any unsprung, rotating mass savings help) and offer small increases in cooling speed. However, they are prone to crack more, especially propagating from the drilled holes. This can be accounted for with a proper rotor design (i.e., pillar and hole location/orientation) to prevent small cracks from propagating all the way to the disc edge. If the rotor is designed correctly and sized properly for the application cracking is minimal. That being said, many designs on the market (I won't name any specifically) arent designed properly (arrangement to prevent crack propagation), machined properly (poor or no chamfering), and are under-sized for the application (thermal mass). This is especially true of those popular in the ricer community.
Now, with all of the previous being my personal/professional opinion, Brembo understands that there are both advantages and disadvantages to X-drilled rotors. We leave it to our customers discretion as to which is used (drilled/slotted/solid-faced). In most OEM situations, it comes down to Marketablility.
-Todd</TD></TR></TABLE>
Todd(Silversnake) is an application's engineer for Brembo U.S. as per his further quotes in the above link.
Modified by 1GreyTeg at 10:37 AM 2/26/2004
But I did read an article on the maufacturing process of the Porsche carbon brake discs. It shows how the pile of metal powder tranform into a disc. It also shows the cast split in half, with all the bumps where the holes are supposed to be.</TD></TR></TABLE>
Ha Ha!
I finally Fuggin found the link!!!
https://honda-tech.com/zerothread?id=655608
And where I remembered this discussion from:
http://corner-carvers.com/foru...ber=1
And what John says: "Pay attention to SilverSnake's posts in this thread on CornerCarver. On the top of Page 2:"
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Silversnake »</TD></TR><TR><TD CLASS="quote">"However, one intersting item is that all of our X-drilled holes are exactly that....drilled.....even the Porsche ones. Its a bit of an urban legend that Porsche "casts-in their holes" for strength. Truth is, when I started with Brembo I thought the same thing. I mentioned it to our Italian resident Applications Engineer. I was kinda surprised myself. He laughed and added, "People seriously think we cast in all of the holes? Wow, I'd love to see the mold for that! No, actually they are all drilled and chamfered post-casting. "</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Silversnake »</TD></TR><TR><TD CLASS="quote">My personal opinion is with today's materials its mostly for bling. there are some slight benifits to it, but there are also some negatives. There have been Brembo/Porsche tests to show that x-drilled rotors increases first effectiveness in wet conditions. Assuming there is enough mass for thermal capacity of the application, X-drilling can save a slight amount of weight (although any unsprung, rotating mass savings help) and offer small increases in cooling speed. However, they are prone to crack more, especially propagating from the drilled holes. This can be accounted for with a proper rotor design (i.e., pillar and hole location/orientation) to prevent small cracks from propagating all the way to the disc edge. If the rotor is designed correctly and sized properly for the application cracking is minimal. That being said, many designs on the market (I won't name any specifically) arent designed properly (arrangement to prevent crack propagation), machined properly (poor or no chamfering), and are under-sized for the application (thermal mass). This is especially true of those popular in the ricer community.
Now, with all of the previous being my personal/professional opinion, Brembo understands that there are both advantages and disadvantages to X-drilled rotors. We leave it to our customers discretion as to which is used (drilled/slotted/solid-faced). In most OEM situations, it comes down to Marketablility.
-Todd</TD></TR></TABLE>
Todd(Silversnake) is an application's engineer for Brembo U.S. as per his further quotes in the above link.
Modified by 1GreyTeg at 10:37 AM 2/26/2004
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From: IL
Re: (1GreyTeg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SilverSnake »</TD></TR><TR><TD CLASS="quote">However, one intersting item is that all of our X-drilled holes are exactly that....drilled.....even the Porsche ones. Its a bit of an urban legend that Porsche "casts-in their holes" for strength. Truth is, when I started with Brembo I thought the same thing. I mentioned it to our Italian resident Applications Engineer. I was kinda surprised myself. He laughed and added, "People seriously think we cast in all of the holes? Wow, I'd love to see the mold for that! No, actually they are all drilled and chamfered post-casting.</TD></TR></TABLE>
As mentioned, I've seen the pics of the mold for the Porsche carbon discs before. I dunno if Brembo is Porsche OEM supplier. But if I could find that article again I would definitely scan the pics and post it up.
As mentioned, I've seen the pics of the mold for the Porsche carbon discs before. I dunno if Brembo is Porsche OEM supplier. But if I could find that article again I would definitely scan the pics and post it up.
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From: kuidaore
Re: (Wai)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Wai »</TD></TR><TR><TD CLASS="quote">
As mentioned, I've seen the pics of the mold for the Porsche carbon discs before. I dunno if Brembo is Porsche OEM supplier. But if I could find that article again I would definitely scan the pics and post it up. </TD></TR></TABLE>
Yeah I saw him post this about that topic:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SilverSnake »</TD></TR><TR><TD CLASS="quote">I work for Brembo. All Porshe rotors, with the exception of the Ceramic, are cast and machined by Brembo. I am not sure at which plant the rotors are cast, but they are Brembo parts. Porsche only does their ceramic rotors in house. For ceramics, we use our own technology, Ceramic Composite Matrix (CCM), on applications such as the Enzo and 360 Challenge Stradale.</TD></TR></TABLE>
As mentioned, I've seen the pics of the mold for the Porsche carbon discs before. I dunno if Brembo is Porsche OEM supplier. But if I could find that article again I would definitely scan the pics and post it up.
</TD></TR></TABLE>Yeah I saw him post this about that topic:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SilverSnake »</TD></TR><TR><TD CLASS="quote">I work for Brembo. All Porshe rotors, with the exception of the Ceramic, are cast and machined by Brembo. I am not sure at which plant the rotors are cast, but they are Brembo parts. Porsche only does their ceramic rotors in house. For ceramics, we use our own technology, Ceramic Composite Matrix (CCM), on applications such as the Enzo and 360 Challenge Stradale.</TD></TR></TABLE>
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From: AZ
Re: (1GreyTeg)
I would disagree with the fact that drilled rotors by major manufacturers are more prone to cracking. If they are drilled in the proper fashion, the area around the hole is cold worked and thus increased strength compared to the areas that havent been cold worked. If they are drilled improperly in the wrong direction or the rotors have been improperly treated they are prone to cracking.
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From: Kelowna Canada
Re: (gary201147)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gary201147 »</TD></TR><TR><TD CLASS="quote">I would disagree with the fact that drilled rotors by major manufacturers are more prone to cracking. If they are drilled in the proper fashion, the area around the hole is cold worked and thus increased strength compared to the areas that havent been cold worked. If they are drilled improperly in the wrong direction or the rotors have been improperly treated they are prone to cracking.</TD></TR></TABLE>
COLD WORKING is generally done by drawing or rolling metal like copper. This will raise strength and reduce malleability.
You mind explaining how drilling performs this same function?
I think you are talking out of your ***.
BPR - who works with metal every single day
COLD WORKING is generally done by drawing or rolling metal like copper. This will raise strength and reduce malleability.
You mind explaining how drilling performs this same function?
I think you are talking out of your ***.
BPR - who works with metal every single day
Joined: Sep 2003
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From: FUCK THEIVES, va, USA
Re: (gary201147)
well about the porshce brakes they do break, my friends dad has a 911 and i know he replaced the rotors up front once already casue they were breaking, and it just tears thru pads (which are SO expenisvie)
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From: AZ
Re: (Big Phat R)
Cold working is commonly performed by drawing or rolling but it is not the ONLY way cold work is done. Cold working is deforming while strengthening, increasing the number of dislocations in the polycrystalline aggragate. It may not be the intention of manufacturers to cold work the rotors by drilling them but it IS a consequence of drilling them, and therefore, I stand by my statement that cracks are not likely to form along the drilled portions of the rotor.
I'm sure you are aware of the microstructure of metals just by working with them everyday
<- Who feels attacked
I'm sure you are aware of the microstructure of metals just by working with them everyday
<- Who feels attacked
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From: RIP Craig Jones
Re: (gary201147)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gary201147 »</TD></TR><TR><TD CLASS="quote">increasing the number of dislocations in the polycrystalline aggragate. </TD></TR></TABLE>
Oh the horror... make it stop! Oh dear god *hides eyes from the light*
RJ - having flashbacks
Oh the horror... make it stop! Oh dear god *hides eyes from the light*
RJ - having flashbacks
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From: IL
I spent about 2 hrs diggin thru my stack of magazines trying to find that article about the manufacturing process of Porsche's carbon ceramic brakes. But I couldn't find it.... 
But anyway, it seems that carbon discs are under a totally different process that the holes are cast in place when the shape is formed based on the article and pictures that I read; while other OEM Porsche discs are drilled afterwards based on the post by the guy who works for Brembo.
I still suspect that for some *non-OEM* discs, the holes might still be cast in. :dunno:
But anyway, it seems that carbon discs are under a totally different process that the holes are cast in place when the shape is formed based on the article and pictures that I read; while other OEM Porsche discs are drilled afterwards based on the post by the guy who works for Brembo.
I still suspect that for some *non-OEM* discs, the holes might still be cast in. :dunno:
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From: Drinking Beer, UT
Re: (ITR5874)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITR5874 »</TD></TR><TR><TD CLASS="quote">Thanks for all the replies.... So what can we say ?
Blanks or slotted for track application ? </TD></TR></TABLE>
Blanks for anything less than a grand-am car.
Blanks or slotted for track application ? </TD></TR></TABLE>
Blanks for anything less than a grand-am car.
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