drilled rotors, low profile tires

[567234ta]

low profile tires= less performance
drilled and slotted rotors= rotor failure

notes: if you plan on driving in any aggressive manner at all, racing whatever, dont use drilled and slotted.

edit: notes: if you plan on driving in any aggressive manner at all, racing whatever, dont use drilled and VENTED i meant

 

[POWERED by HONDA]

It's not wise to use cross-drilled, drilled AND slotted rotors... but using just slotted rotors is fine...

Don't real race cars use slotted rotors? I swear race cars such as the Champcars use slotted rotors.

I also run slotted rotors on my daily driver. It has a few track events and currently has about 80,000-100000 miles on them (!!!). When I need to change my rotors on my NSX, I will go slotted.

 

[Yellow Rose]

low profile tires= less performance

???

drilled and slotted rotors= rotor failure

Not a 100% true statement. When I had OEM-sized rotors, they were slotted and even under heavy track use did not give me any problems. With my current drilled rotors after two years (including track events) there are no problems. As another data point, solid rotors can fail too.

It's not wise to use cross-drilled

Be sure and warn Porsche, Ferrari, Mercedes-Benz, Lambo, McLaren, etc......their cars come from the factory with drilled rotors that are Brembo or Brembo-derivative.

 

[kenjiMR]

I think drilled and slotted rotors would be prone to cracking and failure earlier than a blank rotor close to 99% of the time. Also, I don't think any of the rotors sold with the cars you mentioned are likely to be "drilled". Instead the holes are cast and beveled with the holes for unsprung weight reduction and balanced heat dissapation due to size of the rotor. I think for OEM sized NSX rotors, it seems that drilled rotors don't have any significant benefit if you use brake pads such as Carbotechs etc.

Andy, didn't you work for Carbotech? If so, I'm really suprised by your comments.

low profile tires= less performance
drilled and slotted rotors= rotor failure

Not a 100% true statement. When I had OEM-sized rotors, they were slotted and even under heavy track use did not give me any problems. With my current drilled rotors after two years (including track events) there are no problems. As another data point, solid rotors can fail too.

It's not wise to use cross-drilled

Be sure and warn Porsche, Ferrari, Mercedes-Benz, Lambo, McLaren, etc......their cars come from the factory with drilled rotors that are Brembo or Brembo-derivative.

 

[kenjiMR]

oh for what its worth, I currently am using powerslot rotors up front since they are relatively cheap. I replaced my OE front rotor due to cracking from severe track use using Carbotech P+ brake pads.

 

[Yellow Rose]

The Other A

Andy, didn't you work for Carbotech? If so, I'm really suprised by your comments.

No. Even if I did, I stand behind my comment. Those premier exoticars come with drilled rotors from the factory for a reason, so they gotta be thinking something right.

You are thinking of Andie Lin, who since left Carbotech to start Cobalt. Cobalt was one of the sponsors of NSXPO 2002.

 

[kenjiMR]

Re: The Other A

I think you missed the meat of my reply.

drilled is not the same as casted. Rotor size and bling bling factors are still present in P-cars and Ferraris.

From engineering standpoint, I don't think most aftermarket manufacturers have done nearly the research Ferrari or Porsche has done on their brake components. Just saying that drilled is good because P-cars and F-cars use them doesn't make them good for you. If you go to various professional racing events, you will see many race cars that do not use drilled rotors whatsoever.

Andy, didn't you work for Carbotech? If so, I'm really suprised by your comments.

No. Even if I did, I stand behind my comment. Those premier exoticars come with drilled rotors from the factory for a reason, so they gotta be thinking something right.

You are thinking of Andie Lin, who since left Carbotech to start Cobalt. Cobalt was one of the sponsors of NSXPO 2002.

 

[Yellow Rose]

Good Enough For Me

drilled is not the same as casted

I know that. I think that 99% of the people savvy about brakes say "drilled" with the understanding that the rotors have the holes cast into the blanks, and during the machining process the holes are chamfered to eliminate the stress-riser associated with a square edge where the hole meets the wear surface of the rotor. Anyone who would take a solid rotor and convert it by simply drilling holes between the cooling vanes, is an idiot.

Rotor size and bling bling factors are still present in P-cars and Ferraris.

Gonna show some ignorance here, but what is bling-bling with those two cars as it relates to brakes?

From engineering standpoint, I don't think most aftermarket manufacturers have done nearly the research Ferrari or Porsche has done on their brake components.

Actually, for the Italian car, the brakes are by Brembo. In fact, for that Italian race team, Brembo develops the brakes, not Ferrari. Ferrari may have a hand in design such as location of the caliper to minimize CG but the actual development of the technology is by Brembo. Therefore, since the world's leading brake component manufacturer supplies brakes to Ferrari, my phrase of "if it is good enough for Ferrari it is good enough for me" has valid credability. Especially since Brembo is showing up on more and more production cars - WRZ, Nissan's Z, G35 (?), Evo, Mustang Cobra, etc.

Just saying that drilled is good because P-cars and F-cars use them doesn't make them good for you.

Yes it does because I (and you and fellow NSXers) am not a professional race car driver; therefore, for occasional HPDEs, solid rotors are not promised to last any longer than rotors with holes in them.

If you go to various professional racing events, you will see many race cars that do not use drilled rotors whatsoever.

See previous comment.

 

[kenjiMR]

Re: Good Enough For Me

I agree on your points and I know that Brembo is a recognized leader in braking technology.

Since we are discussing NSX without big brake kits, I still disagree that any drilled rotor would provide any significant benefit for OE sized rotor.

The Brembo kit for the NSX that Comptech sells does rule. How Brembo does it is much more complex than what we could deduce here.

Oh, regarding bling-bling for P/F cars? I always assumed that P/F cars also cater to the bling bling rich man crowd. holey rotors look cool. Sacrifice rotor/pad life to bling bling factor.

drilled is not the same as casted

I know that. I think that 99% of the people savvy about brakes say "drilled" with the understanding that the rotors have the holes cast into the blanks, and during the machining process the holes are chamfered to eliminate the stress-riser associated with a square edge where the hole meets the wear surface of the rotor. Anyone who would take a solid rotor and convert it by simply drilling holes between the cooling vanes, is an idiot.

Rotor size and bling bling factors are still present in P-cars and Ferraris.

Gonna show some ignorance here, but what is bling-bling with those two cars as it relates to brakes?

From engineering standpoint, I don't think most aftermarket manufacturers have done nearly the research Ferrari or Porsche has done on their brake components.

Actually, for the Italian car, the brakes are by Brembo. In fact, for that Italian race team, Brembo develops the brakes, not Ferrari. Ferrari may have a hand in design such as location of the caliper to minimize CG but the actual development of the technology is by Brembo. Therefore, since the world's leading brake component manufacturer supplies brakes to Ferrari, my phrase of "if it is good enough for Ferrari it is good enough for me" has valid credability. Especially since Brembo is showing up on more and more production cars - WRZ, Nissan's Z, G35 (?), Evo, Mustang Cobra, etc.

Just saying that drilled is good because P-cars and F-cars use them doesn't make them good for you.

Yes it does because I (and you and fellow NSXers) am not a professional race car driver; therefore, for occasional HPDEs, solid rotors are not promised to last any longer than rotors with holes in them.

If you go to various professional racing events, you will see many race cars that do not use drilled rotors whatsoever.

See previous comment.

 

[steveny]

I would think that if drilled rotors heated up as much as non drilled rotors you would be right about cracking. The drilling of the rotors is the reason they do not get as hot, and thus being less of a chance of cracking or failure.

I run drilled rotors, poterfeild pads, Stainless brake lines, Dali air scoops, and racing brake fluid with no problems. This was not the case with the stock setup I was warping rotors over and over again.

 

[kenjiMR]

I don't know if your warping problems is due to the cooling provided by the holes, but I have a feeling that large brake kits with holes are to minimize warping and weight instead of increasing braking capacity. The rotor will expand and contract in a more uniform manner. These are all my guesses, but there is an infamous thread that has been saved over at cc.com which is worth a read regarding this issue:

http://corner-carvers.com/altimathread.php.html

read toward the middle.

I would think that if drilled rotors heated up as much as non drilled rotors you would be right about cracking. The drilling of the rotors is the reason they do not get as hot, and thus being less of a chance of cracking or failure.

I run drilled rotors, poterfeild pads, Stainless brake lines, Dali air scoops, and racing brake fluid with no problems. This was not the case with the stock setup I was warping rotors over and over again.

 

[nsxtasy]

I think it's funny that everyone goes off in a tizzy when a newbie posts something that shows that he doesn't know what he's talking about. Did everyone overlook that he said "low profile tires = less performance"? That's one of the silliest statements I've heard. What qualifies as "low profile tires"? The 40-profile stock tires on the '02-03 NSX? The 50-profile stock tires on the '91-93 NSX? Most folks would consider all of them to be low profile tires (albeit some lower than others). Gee, I think I better go replace the tires on my NSX with some nice 165/80-15 rubber.

As for the rotors, I've them all (I'm on my twelfth set of front rotors on my NSX) - rotors with solid faces, rotors with holes, rotors with slots, and even rotors with holes and slots. And they all crack. I've done it. And I have observed nothing to indicate that any one type cracks quicker than another. Those "99 percent" statements just don't hold up when you look at the empirical evidence.

I don't know if your warping problems is due to the cooling provided by the holes, but I have a feeling that large brake kits with holes are to minimize warping and weight instead of increasing braking capacity.

No, the primary benefit of large brake kits is greater dissipation of heat, so that it won't cause the rotors to crack or the fluid to boil.

Those who are mentioning "warping" probably haven't read this Stoptech white paper.

The rotor will expand and contract in a more uniform manner.

That is the advantage of some big brake kits - not because they are larger, but because they include floating hats in a two-piece design. This lets the outer "ring" of the rotor faces expand as it gets hot, without being fixed to a smaller center "hub" (hat) that can't expand in the same way. One-piece rotors can't expand at the same rate, so they are more susceptible to cracking.

 

[567234ta]

i must have been sleepy when i first posted this, i meant vented and drilled, slotted may be useful if your running rally and a lot of mud is present.
bigger rotors are better, for many reasons, drilling them is only for looks unless your running brake pads from 1956.

i see a lot of people here buying them because the impression of better braking ability is put with them.
so i wanted to raise this issue and get the truth of it out there for everyone.
my #1 reason for doing so is that safety is involved, and i see a lot of misleading information regarding braking.


nice information im seeing here now
taken from the link above-
PREVENTION

There is only one way to prevent this sort of thing - following proper break in procedures for both pad and disc and use the correct pad for your driving style and conditions. All high performance after market discs and pads should come with both installation and break in instructions. The procedures are very similar between manufacturers. With respect to the pads, the bonding resins must be burned off relatively slowly to avoid both fade and uneven deposits. The procedure is several stops of increasing severity with a brief cooling period between them. After the last stop, the system should be allowed to cool to ambient temperature. Typically, a series of ten increasingly hard stops from 60mph to 5 mph with normal acceleration in between should get the job done for a high performance street pad. During pad or disc break-in, do not come to a complete stop, so plan where and when you do this procedure with care and concern for yourself and the safety of others. If you come to a complete stop before the break-in process is completed there is the chance for non-uniform pad material transfer or pad imprinting to take place and the results will be what the whole process is trying to avoid. Game over.

 

[nsxtasy]

i see a lot of misleading information regarding braking.

So do I!

 

[Nimbus]

This is all too funny.

 

[567234ta]

and what i mean by low profile is not the stock size tire that comes with it, i mean when you change it to a much lower profile so you can have a huge rim for looks you suffer traction loss.
im trying to keep within basic english and not make it something you have to have 4 years of reading to understand every possible tire combination that would fit and the values of them.

if people here wanted to read books about the physics of braking systems they probably would have before purchasing aftermarket rims, brakes, with kinda just going with what seems common knowledge.

so instead of calling me a newbie lets keep it friendly as if i were at your house talking with you about it.
and lets keep it simple to understand as a resource for people who are seeking the best braking kits and upgrading their cars so as not to be taken astray from what works and what doesnt.

 

[kenjiMR]

Don't you think I already knew what you wrote?

We were not originally talking about BBKs. BBKs have all sorts of advantages, but they are also often designed for serious track work and are inspected regularly. 99% is close to 100%. I was saying that blanks would not provide any significant advantage in braking capacity over slotted or drilled in a street car.

Many BBKs including the new Porsche brakes have all sorts of technology not found in typical car brake systems. One person above stated after adding drilled rotors, he has had less warping. I believe that, but I don't believe he has gained any braking capacity either. More likely lost braking capacity, but gained less warping.

I think it's funny that everyone goes off in a tizzy when a newbie posts something that shows that he doesn't know what he's talking about. Did everyone overlook that he said "low profile tires = less performance"? That's one of the silliest statements I've heard. What qualifies as "low profile tires"? The 40-profile stock tires on the '02-03 NSX? The 50-profile stock tires on the '91-93 NSX? Most folks would consider all of them to be low profile tires (albeit some lower than others). Gee, I think I better go replace the tires on my NSX with some nice 165/80-15 rubber.

As for the rotors, I've them all (I'm on my twelfth set of front rotors on my NSX) - rotors with solid faces, rotors with holes, rotors with slots, and even rotors with holes and slots. And they all crack. I've done it. And I have observed nothing to indicate that any one type cracks quicker than another. Those "99 percent" statements just don't hold up when you look at the empirical evidence.

No, the primary benefit of large brake kits is greater dissipation of heat, so that it won't cause the rotors to crack or the fluid to boil.

Those who are mentioning "warping" probably haven't read this Stoptech white paper.

That is the advantage of some big brake kits - not because they are larger, but because they include floating hats in a two-piece design. This lets the outer "ring" of the rotor faces expand as it gets hot, without being fixed to a smaller center "hub" (hat) that can't expand in the same way. One-piece rotors can't expand at the same rate, so they are more susceptible to cracking.

 

[kenjiMR]

Also from my understanding, BBKs provide overall larger contact surface area with the brake pad which would require less pressure from the braking system which in turn would reduce the actual temperature at contact point. The larger the contact patch with the brake pads, the faster the brake can absorb the energy. To reducing contact with the pad would have to have additional benefits which I am not certain of... my theories were presented above.

 

[kenjiMR]

I would think that if drilled rotors heated up as much as non drilled rotors you would be right about cracking. The drilling of the rotors is the reason they do not get as hot, and thus being less of a chance of cracking or failure.

Do you really believe the rotors get less hot just because they have tiny holes in them?
Cracking is caused by the expansion and contraction of the metal which occurs with any rotor.

 

[nsxtasy]

and what i mean by low profile is not the stock size tire that comes with it, i mean when you change it to a much lower profile so you can have a huge rim for looks you suffer traction loss.

That is quite possible and I agree with you. Thanks for the clarification.

Originally posted by kenjiMR
99% is close to 100%. I was saying that blanks would not provide any significant advantage in braking capacity over slotted or drilled in a street car.

I agree with you on that. What I took issue with was this statement:

Originally posted by kenjiMR
I think drilled and slotted rotors would be prone to cracking and failure earlier than a blank rotor close to 99% of the time.

which, as I mentioned, is not consistent with my experience.

 

[kenjiMR]

That which, as I mentioned, is not consistent with my experience.

You're probably right. I have a set of slotted on my NSX now and a set of drilled on my MR2 (from prior owner). My theory is totally unfounded regarding durability, but its not hard to think that crap drilled rotors would last lest. The photo may help illustrate how my rotors on my MR2 almost look.

 

[nsxtasy]

The photo may help illustrate how my rotors on my MR2 almost look.

Yes, those are ready for replacement. In fact, they're probably just starting to make a bit more noise on the street, with cracks that size.

If anything, the holes make the cracks easy to find, because that's where they form. But they are fairly easy to spot on slotted and solid rotors too.

 

[Yellow Rose]

BBK

Since we are discussing NSX without big brake kits, I still disagree that any drilled rotor would provide any significant benefit for OE sized rotor.

Thus the premise for our "disagreement".....my posts are in the context of big drilled Brembos, which I have.

 

[Yellow Rose]

I think it's funny that everyone goes off in a tizzy when a newbie posts something that shows that he doesn't know what he's talking about. Did everyone overlook that he said "low profile tires = less performance"?

I don't think anybody has "gone off in a tizzy", Kenji and I were just expressing different viewpoints of drilled rotors....and we did so w/o any name calling. To answer your question if everyone overlooked the low profile comment, that answer is "no". Check my first post to this thread and you'll see that I questioned the original post with "???". But at least I didn't say "That's one of the silliest statements I've heard." I thought it, but I didn't say it.

 

[Soichiro]

>>slotted may be useful if your running rally and a lot of mud is present.

So the slots are designed for cleaning mud off the rotors? Thanks for this information, I was confused because all the brake manufacturers, and the brake physics books I've read say the slots wipe the pads of unwanted outgassing and other materials.

>>when you change it to a much lower profile (tire) ... you suffer traction loss.

I thought traction was dependant on rubber compound, inflation pressure, internal construction and tread design. Stupid me, it's the height of the sidewall that determines traction. I wonder if any race teams or auto manufacturers know this stuff?

A larger wheel (needed with lower profile tires) may add weight to the car but more weight equals more traction in my auto physics handbook.