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Literature from "unbiased" sources that "sell" the said parts... heheh...
Do you think they would tell their potential customers NOT to buy the more expensive rotors... Wake up...
Less surface contact area = less friction = less stopping power. (simple physics)
It also equals significantly lower rotor life due to cracking from the heat cycles.
Cross-drilling = fashion statement on street cars.
Why?
Since we do not use any exotic materials for pad and rotor manufacturing that cause extreme amounts of excess gasses to be created. Not only that, but slotting the rotors more effectively evacuates these gasses than cross-drilling does, leaves more contact area and is not prone to cracking like drilled rotors are...
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"Cryo has nothing to do with performance", what are you smoking?  Go to www.carbotecheng.com while your suggesting reading material. Look in their FAQ section for the articles on cyrogenically treating rotors. Odd that racing teams are doing it all the time if it doesn't impact the performance
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are you guys done yet...i came in here looking for advice, not to witness this drama...lets stick to the point and quit talking $hit...can't you guys just agree to disagree....? i also am looking for rotors and have heard what you both of you are saying from others....who's right? WHO CARES!!!! everyone has their own preferences. just speak your opinion and be done with it....you're wasting everyone else's time that comes in here.....so please, with sugar on top, can you two play nice....... 
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Originally posted by DemonSVT:
Not only that, but slotting the rotors more effectively evacuates these gasses than cross-drilling does, leaves more contact area and is not prone to cracking like drilled rotors are... I have a question about that. I would have to believe that cross drilling would leave MORE surface area. Because the pads can only contact the part of the surface that hasnt been grooved down it would seem to me that there would actually be a LOT less surface area to contact. I'm not saying one is better than the other and dont wish to get into the argument that is currently going on. It is highly entertaining as all flame wars are and I dont wish to impede it's progress. Just curious about your statement.
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Look at a rotor the has been grooved compared to one that is drilled.    Same number (or less normally) of arcs, but drilling removes more material and therefore more contact area is lost. The "grooves" are tiny little chamfered channels in the rotor. Starting before the contact area and ending after it. The are not wide at all.
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Actually, less contact area doesn't equal to less friction. I got into this arguement with my friend, and found that this was wrong. Here's why. When you have less surface area to be acted on, you'll have more force per square inch to be counted for. So, when you have less surface area to act on, there are actually more frictional force on the remaining area which will turns out to have the same net frictional force. The easiest way to visualize it is to wrap a block of wood with sandpaper, then measure the force it takes to push it laying flat on the ground; then measure the force it takes to push it laying sideway on the ground. But, because of the added stress, the cross drilled rotors will probably not last as long. Originally posted by DemonSVT:
Less surface contact area = less friction = less stopping power. (simple physics)
It also equals significantly lower rotor life due to cracking from the heat cycles.
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Well said AirKnight, I agree completely.  Furthermore, the cross drilled rotors may actually have greater stopping power because of the additional surface of the edge of the holes (think of a cheese grater). This is the reason that pads will wear faster on them. Also, poorly designed systems will be more fragile than a non-drilled rotor in terms of cracking, and the rotor itself will wear out faster due to less surface area. Heat dispursion will be better in extreme cases -ie in racing, or if you live in the mountains, etc where brake fade is an issue. For the most part though, the minimal benifits of drilled rotors won't be worth the cost and additional wear and tear/durability *on a street car*. If you're that concerned with cooling, brake ducting/ ventilation would be a better investment. -just my $0.02
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Originally posted by AirKnight: Actually, less contact area doesn't equal to less friction. I got into this arguement with my friend, and found that this was wrong. Here's why. When you have less surface area to be acted on, you'll have more force per square inch to be counted for. So, when you have less surface area to act on, there are actually more frictional force on the remaining area which will turns out to have the same net frictional force. The easiest way to visualize it is to wrap a block of wood with sandpaper, then measure the force it takes to push it laying flat on the ground; then measure the force it takes to push it laying sideway on the ground.
But, because of the added stress, the cross drilled rotors will probably not last as long.
Originally posted by DemonSVT:
[b]Less surface contact area = less friction = less stopping power. (simple physics)
It also equals significantly lower rotor life due to cracking from the heat cycles. Airknight, we've had this argument before. What you're saying is true, but I don't think it applies to rotors. We've had this discussion before using the width of a tire. Why aren't we all running on 155mm tires? Using your logic, a 155mm wide tire will have as much grip as a 255mm wide tire. Absolutley false. Why wouldn't we have a tiny ass caliper (using the same amount of pressure as what we have now) with a 1" x 1" brake pad? Theoretically, using your logic, it would brake the same... Absolutely false... John
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[QUOTE] Originally posted by JVT:
we've had this argument before. What you're saying is true, but I don't think it applies to rotors. We've had this discussion before using the width of a tire. Why aren't we all running on 155mm tires? Using your logic, a 155mm wide tire will have as much grip as a 255mm wide tire. Absolutley false.
QUOTE]
Actually rubber behaves differently than most materials, and it IS an exception to this rule. I believe it holds true for all other common materials, however. If surface area really mattered why not just have a brake kit with giant brake pads?
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