rotor/pads

[linksys42]

Hello, I was wondering what the best brake pad/rotor combo is? I was leaning towards the power slot rotors and metal master pads hawk pads. I am pretty hard on my brakes. I like to take twisty highway runs on the back roads in Missouri, but this is my daily driver also. But I don’t want to upgrade to big brakes. Just want to know what the best stock size rotor and pads combo is that wont eat my new rotors that I buy with in a couple of months. Thanks again

 

[Goro21]

I have a set of powerslot rotors on my car now and they are great. Huge improvement over the stockers I had on there.

I would look at the brake/pad sets from Thespeedfactor.com, They have some great "kits," that are reasonably priced.

http://www.thespeedfactor.com/brakekits_dsm2.html

 

[D_Eclipse9916]

Ditto to the speedfactor kit, im running it and havent had a problem, made the car look better and braked a shit load better. When I pulled the stock rotors off they literally fell apart to dust, I was surprised they even braked for the previous owner of the car.

 

[UMR98GSX]

I love my Bremebo slotted/ Hawk HPS combo. It is much better than the stockers. Now I just need to upgrade to stainless lines and DOT 6 fluid.

Anson

 

[linksys42]

Well I am going to replace the stock lines with SS and motul 600c fluid when I do the rotors; I am prob going to go with the power slot rotors unless the brembo slotted are proven to be better. I don’t care about the cost. I just can’t justify the cost of a big brake kit. I am trying to decide between powerslot, brembo, RB performance, AEM for the rotors and R4-S or hawk HPS or just go with the Axis metal masters?

 

[VelocitàPaola]

I went with Axxis ceramic/kevlar pads and Brembo Sport cross-drilled rotors. I know there's been alot of hype surrounding drilled rotors, but I must say - they are truly excellent rotors. The stopping power is unparalleled, and I've never warped them.

If you get these, rest assured in their design. Brembos have chamfered holes to avoid unnecessary wear on the pads. Also, if I remember correctly, the holes are cast with the rotor, rather than drilled afterward, meaning the chances of cracking are very minimal.

I was in the same boat as you a while ago, I didn't want a big brake kit, yet I desperately needed some sort of an upgrade. Take advantage of all the research I already did - this is the best combination, short of a big brake kit, that I could find.


Also... Import Replacement Parts has the lowest prices on authentic Brembo rotors that I could find. They have slotted and OE rotors too, if that's the way you want to go. (http://www.importrp.com/home.php)

 

[steve]

I know you say you don't want to upgrade to "big Brakes" but you sould really consider getting the dual piston calipers from the AWD cars. If you do some shopping for the calipers it will add <$100 to the cost. On my car I used to go through brakes every 20k from either worn pads or warped rotors. I've got about that on these and they show minimal wear.

Steve

 

[linksys42]

I know you say you don't want to upgrade to "big Brakes" but you sould really consider getting the dual piston calipers from the AWD cars. If you do some shopping for the calipers it will add <$100 to the cost. On my car I used to go through brakes every 20k from either worn pads or warped rotors. I've got about that on these and they show minimal wear.

Steve

I think I am just going to go with the stock big brake kit. Because the more I read the more I see that the slotted and cross drilled rotors are just a gimmick. That the pads are the main source of braking and the size of the rotor (to dissipate heat) larger the surface the better the heat dissipation. Am I correct on this? Thanks again

 

[VelocitàPaola]

I think I am just going to go with the stock big brake kit. Because the more I read the more I see that the slotted and cross drilled rotors are just a gimmick. That the pads are the main source of braking and the size of the rotor (to dissipate heat) larger the surface the better the heat dissipation. Am I correct on this? Thanks again

Certainly. The size of the rotors and pads are the primary determinants of braking power. Larger rotors don't always mean optimal heat dissipation, though: that depends on internal venting, alloy composition, etc.

Also, slots and holes aren't necessarily gimmicks. While they don't directly contribute to braking power, they do significantly help with rotor cooling. This is important because, obviously, overheated brakes do not stop as well (I know from experience... ).

There have been a few claims of cross-drilled rotors cracking, which is probably why you think these things are gimmicks. In most cases, those rotors were drilled after the main manufacturing process. If you buy rotors like Brembos, the holes are cast with the rotors, which prevents this.

I can't speak for all manufacturers, but Brembo rotors are found as stock parts on a few Porsches and are TUV (the harsh German government automobile agency) approved.

Your best bet would probably be the AWD "Big Brake" calipers with Brembo Sport rotors and some high end pads (EBC Green Stuffs, Axxis Kevlar/ceramic pads, etc.)

 

[D_Eclipse9916]

Certainly. The size of the rotors and pads are the primary determinants of braking power. Larger rotors don't always mean optimal heat dissipation, though: that depends on internal venting, alloy composition, etc.

Also, slots and holes aren't necessarily gimmicks. While they don't directly contribute to braking power, they do significantly help with rotor cooling. This is important because, obviously, overheated brakes do not stop as well (I know from experience... ).

There have been a few claims of cross-drilled rotors cracking, which is probably why you think these things are gimmicks. In most cases, those rotors were drilled after the main manufacturing process. If you buy rotors like Brembos, the holes are cast with the rotors, which prevents this.

I can't speak for all manufacturers, but Brembo rotors are found as stock parts on a few Porsches and are TUV (the harsh German government automobile agency) approved.

Your best bet would probably be the AWD "Big Brake" calipers with Brembo Sport rotors and some high end pads (EBC Green Stuffs, Axxis Kevlar/ceramic pads, etc.)

Slotted and drilled are gimmicks. Slotted and drilled were for gases when brakes used to have asbestos and it vented these gases. However, slotted and drilled do save a few ounces of weight and look really good.

Also brembos are not cast-drilled. Look up on their FAQ, accordign to them there is no difference. Only Zimmerman brakes are ACTUAL cast-drilled brakes. Unless you are doing serious track duty with these brakes then the brembos will not have a hint of cracking. With any good drilled rotor make sure trhey are chamfered correctly.

 

[VelocitàPaola]

Slotted and drilled are gimmicks. Slotted and drilled were for gases when brakes used to have asbestos and it vented these gases. However, slotted and drilled do save a few ounces of weight and look really good.

They're not gimmicks; but for the light amount of use they see on most cars, I can see how most people would think that. It takes some pretty harsh braking to see the real differences holes/slots make.

Also, there are still quite a few gases that are shed during braking, so holes/slots do help in that respect.

 

[hereitcomes]

Slotted/Drilled rotors are a great performance upgrade.
The holes and slots in the surface help dispurse heat and make for quick and accurate breaking. With either drilled or slotted rotors a semi-metallic pad should be used for the reduced heat buil-up, where ceramic pads are mainly used for OEM style rotors. They work in stopping power but there is much more dust and residue from the pads.

 

[Templisk]

I've got some Porterfield R4S pads, Powerslot rotors, and SS lines on my Talon and I stop quick and straight.

I'm happy with my setup but I still want to brake faster so I'll be going with a big brake setup eventually.

 

[steve]

I'm happy with my setup but I still want to brake faster so I'll be going with a big brake setup eventually.

Technically you have the "Big Brake" setup on your AWD so you be looking for some bigger brakes.

Steve

 

[D_Eclipse9916]

They're not gimmicks; but for the light amount of use they see on most cars, I can see how most people would think that. It takes some pretty harsh braking to see the real differences holes/slots make.

Also, there are still quite a few gases that are shed during braking, so holes/slots do help in that respect.

Hmm I guess doing track time at summit point raceway doesnt qualify me as using harsh braking? . In fact most my friends that do 6-8 track events a season go with blanks as they perform better and do not crack as easily.


.It is also obvious that a larger rotor will give you a larger brake torque (stopping force). But what about cross drilled or slotted rotors? Well the common belief in the main stream is that somehow slotted or cross-drilled rotors allow for better performance by handling heat. This is 100 percent false. The individuals involved in such fallacies mention that air through the holes works to cool the rotor (convective heat transfer into the air from the rotor). The issue is that from physics we know that metal transfers heat better then air by a significant amount. (The larger mass of the rotor becomes more important then the larger surface area of the rotor in any situation other then the optimal. Cross drilling is not an optimal manner of creating metal to air transfer through larger surface areas. There is not much airflow through the holes.) As such the rotor begins to work as a heat sink. Now by cross drilling or slotting we are decreasing the overall amount of metal to transfer this heat to. Clearly we are decreasing performance of the rotor to dissipate heat amongst itself. We are also damaging the brakes structural rigidity. The iron in a brake rotor is made of a crystalline structure. By drilling holes in said surface we cut the end grains creating a situation that breeds cracks. Furthermore, even if we were to cut the rotors correctly to avoid cutting the end grains structural rigidity is still decreased. The temperature around the holes will be slightly less then that of the entire rotor leading to temperature stress. Moreover, the decreased mass will result in lowered rigidity. Lastly, the holes of a cross-drilled rotor decrease the area of the pad that contacts the rotor. This concentrates the heat more on certain areas of the pad (similar to the idea of using a smaller pad where the pad heats up more quickly).
So what do cross drilled and slotted rotors accomplish? Well cross-drilled does not do anything for a car but perhaps give you a certain bling look. In a motorcycle or other extremely light vehicle the decrease in rotational inertia and unsprung mass might perhaps be useful (once other more efficient avenues are exhausted). However, in a street car or race car the speeds and weight of such vehicles will make the relatively miniscule decrease be outweighed by the need for more heat dissipation.

 

[linksys42]

That’s what I needed to hear, so I will just go with blanks and maybe the big brake set-up with the hawk hps or the Axis metal masters pads. Should I go with a certain manufacture for the blanks? Thanks

 

[VelocitàPaola]

Very good D_Eclipse9916, but unfortunately, not everything you said was entirely accurate. linksys42, I would think twice before purchasing anything.

To begin with, yes, metal does transfer heat better than air. With solid rotors, however, the heat has nowhere to go; so surface area does play a major role in cooling here. Both holes and slots increase surface area (holes more so), thus increasing any cooling effects.

The heat sink analogy was good, but heat sinks take heat away from a source; rotors just keep it concentrated in the same spot.

While discussing heat transfer, you forgot to mention that this isn't just any air removing heat from the rotors: it's moving air. This is another factor that significantly increases cooling. Moving air has a greater potential to cool through convection, since more air molecules are passing over the heated region - just like you said D_Eclipse9916. It's the same principle behind wind chill.

If the rotor has been designed properly (as many of the higher quality rotors are) with respect to internal venting and hole placement/quantity, there is a noticeable difference between these and solid rotors.

The design of the rotor also plays a role in whether or not any hot/cool spots develop on the rotor itself, as D_Eclipse9916 mentioned. Quality drilled/slotted rotors are sufficiently capable of maintaining an even heat distribution, thus preventing hot spots and brake equipment degradation.

Also, cast metals do not have any "crystalline structure" or a grain to them. The casting procedure means the metals were molten (and thus homogeneous), and then poured into a mold. One might only notice a "grain" in folded or forged metals (i.e. Damascus steel).

Cutting (or resurfacing) cross-drilled/slotted rotors poses no threat to the rotor since any reputable manufacturer will have chamfered the areas reasonably enough to prevent damage.

The rigidity of a rotor has nothing to do with these ethereal "grains" or the total mass, but rather the internal structure and alloy composition. If mass were the only determinant of rigidity, then aluminum should be much weaker than steel - in fact, it is not.

Finally, while the holes/slots do slightly diminish the total pad-to-rotor contact area, they're small enough where this is negligible. The effect of the holes/slots completely counteract the minuscule loss of surface area. This also does not concentrate heat on the pad, rather, the holes/slots tremendously help the pads shed heat.

I have never seen any slotted rotors crack, and I have only heard of some lower quality cross-drilled rotors doing the same.

"So what do cross drilled and slotted rotors accomplish?"

Besides all that I mentioned above (the cooling effect, etc.), both cross-drilled and slotted rotors, prevent gases from being trapped between the disc surface and the pads. They also continuously de-glaze the pads by removing the top-most layer of liquefied brake material. This effect provides a consistently fresh pad surface for increased brake performance. (this is paraphrased directly from the Brembo site)

The weight differences (especially with cross-drilled rotors) is also significant enough. While maybe you won't be counting the ounces shaved off your brake equipment for normal street use, it is enough of a difference to matter to Porsche/Ferrari owners and even F1 cars.

Also, keep in mind that many rotor manufacturers allocate their lowest grade of alloys for OE-style/solid discs. The slotted and cross-drilled variations are often steps up from the solid rotors and, in most cases, are made of better alloys, capable of better heat transfer, rigidity, and resistance to warpage.

In any case, whichever route you decide to take, remember what counts when it comes to braking. I've been emphasizing "quality" and "design" alot in this post, and that's because those are the most important factors. Don't expect much from $30 Autozone rotors; look for companies that are established and that have put in the time and research to make a better product.

Under no circumstances was I advocating buying cheaper rotors and having somebody with a drill press make a few holes in them.


Sorry for all that; this all probably deserved a different thread altogether (of which I know there are already many on this topic). If anyone has any more reasons why they think their OE-style rotors are better, don't thread hi-jack, PM me instead.

 

[linksys42]

its not thread hi-jacking really, its good too get different info from different sources. to take it all in account and determine what is right and what is bull ####. and thanks for the info.

 

[VelocitàPaola]

As long as everything that has been said is useful to you, then I suppose it's not thread hi-jacking. I hope it all helped you make a more informed decision. Good luck.

 

[1LE]

$10 (maybe they're up to $15 by now ) Napa rotors, SSB brake lines (something DOT approved of course), Porterfield R-4E pads, and Castrol SRF brake fluid.

 

[linksys42]

$10 (maybe they're up to $15 by now ) Napa rotors, SSB brake lines (something DOT approved of course), Porterfield R-4E pads, and Castrol SRF brake fluid.

this is what you run on the street or just for track days? how long do the rotors hold up?

 

[underradar92]

$10 (maybe they're up to $15 by now ) Napa rotors, SSB brake lines (something DOT approved of course), Porterfield R-4E pads, and Castrol SRF brake fluid.

Granted my 1g rotors are smaller but, I ran 1 month old napa rotors/ebc red stuff pads at a track day & broke a rotor on the warm-up lap. (Road America, cold day in october) I wouldn't recommend that.

 

[1LE]

this is what you run on the street or just for track days? how long do the rotors hold up?

That's what I drive on the street and track. Surprisingly, the R4-E's work better cold than the R4-S. Rotors will hold up for 2 sets of brakes pads. R4-E's get really noisy though if you get any dirt/dust/rust on the rotor.

 

[silvah_gsx]

Out of curiosity, why is it that people always seem to opt for HAWK HPS pads and not the HP-Plus?

Rotor wear won't be an issue as I'm getting slotted Brembos as well, but is there some other issue of which I am not aware?

 

[eclipsegsx1736]

I think most run the Hawk HPS for an agressive street pad, and step up to the Porterfield R4-E for time trial/road racing. I'll eat any rotor quick, but for a track day it's worth it. If you fade an R4-E, you've got other problems.