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SLotted rotors? Any good or costhmetic only?

I run Brembo plain rotors with mintex pads. I find that E-0 callipers feel like they grip better. I had same set up on my SE with E-1 SVT brakes and they felt weaker. Used drilled rotors before and felt no difference, for looks only.
 
Rara said:
Except it in most cases, including ALL cases for contour rotors, it isn't an improvement. The holes decrease the pressure diffierential from the inside to the outside of the vents, dropping overall cooling airflow, which DECREASES heat rejection from the rotor. Not to mention adding lots and lots of stress concentrations all across the face of the rotor leading to inevitable cracking.

Seriously, are you this dense? Or did you just spend a bunch of money on drilled rotors and are doing everything you can to justify the purchase in your mind?
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Show me your tests,oh wait there are none. I mean you are the person who said it produced minimal gains,then a post later contradicted yourself.You also helped engineer OEM car parts,you know the things that most people rip off their cars the first month of owning them. Just look around these forums,oh yeah all of us are keeping our cars stock.LMAO

Until then all of the above posts are just hearsay and personal opinion.
 
SVTDEMON said:
Show me your tests,oh wait there are none. I mean you are the person who said it produced minimal gains,then a post later contradicted yourself.You also helped engineer OEM car parts,you know the things that most people rip off their cars the first month of owning them. Just look around these forums,oh yeah all of us are keeping our cars stock.LMAO

Until then all of the above posts are just hearsay and personal opinion.
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Get a life!!

Or do you enjoy p****** against the wind. The more you post, the stupider you look.
 
SVTDEMON said:
Show me your tests,oh wait there are none. I mean you are the person who said it produced minimal gains,then a post later contradicted yourself.You also helped engineer OEM car parts,you know the things that most people rip off their cars the first month of owning them. Just look around these forums,oh yeah all of us are keeping our cars stock.LMAO

Until then all of the above posts are just hearsay and personal opinion.
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First, any tests I've been involved with are proprietary, and can't be posted for legal reasons. Second, I said minimal gains because there are very few specific rotor applications where there are improvements. GM put out an SAE paper a few years with some testing on some Corvette rotors that showed an improvement in cooling coefficient, but the paper was very vague about the specifics of what was done, and whether the rotors were even of the same design or not. And there are a few other high-end applications where the design work has been done to utilize the holes to improve airflow rather than hurt it.
Third, and most important, even in cases where improvements are possible, you won't see any evidence of it in normal street driving.

And finally, WTF does what people change on thier cars in the aftermarket have to do with the performance? People put larger wheels on because they look good, but the heavier weight, and increased polar moment of inertia means the car accelerates and brakes worse than stock. People buy new tires, and most of the time get a less grippy tire, because its hard to find a DOT tire that is more grippy than the OEM BFG KDW that came on the CSVT toward the end. People put gigantic wings on the back of thier cars that do nothing but hurt performance. People change out stuff on their cars for all sorts of reasons, and appearance is a HUGE one of those reasons.

The bottom line is that you won't find a contour rotor that performs better when drilled compared to the same rotor without holes, and said drilled rotor will crack and fail significantly quicker than either a plain faced or slotted rotor.
 
SVTDEMON said:
Show me your tests,oh wait there are none. I mean you are the person who said it produced minimal gains,then a post later contradicted yourself.You also helped engineer OEM car parts,you know the things that most people rip off their cars the first month of owning them. Just look around these forums,oh yeah all of us are keeping our cars stock.LMAO

Until then all of the above posts are just hearsay and personal opinion.
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You know he also does race parts right? Oh yeah, before I move on, you can put spaces after punctuation, in fact, spaces belong there.

Now, you are arguing basic principles in physics and thermodynamics, you don't exactly need an engineering degree from MIT and a stack of tests to figure this one out. This is high school level stuff. Only reason there ever was for slotting/cross-drilling was looks and off-gassing. I used to think they were still functional, but it is like it has been said on here before, newer brake pad compounds don't function the same way as old brakes. Now, when brakes heat up, the air around them heats up. Hot air is less dense than cold air, which means there is less air in equal volumes of hot and cold air. In brakes, they are designed to pull cool air into the rotor and exhaust hot air. When you drill a rotor, you are adding extra holes in them, and changing the airflow characteristics of the rotor, meaning that they cannot pull in cold air and exhaust hot air as efficiently. This has always been a problem with cross drilling rotors, even when it was functional to assist off-gassing. A rotor has to be specifically designed to function with cross-drilling and its airflow characteristics. Now, even at rest, cross-drilling still doesn't help heat dissipation because you are reducing the surface area that can be exposed to cool air.

You aren't really paying any attention to the physics RARA gave you earlier. I take it RARA was right and you spent big money on rotors and are trying to convince yourself they werent just for looks. Just remember, most aftermarket "performance" parts, are just for looks. It's not like polished stainless steel mufflers perform any better than normal mufflers.
 
You can rack that amount up in 3 years. He has been here 10! Post count doesn't mean he knows it all or doesn't so it's irrelevant.

This thread turned out to be very involved. I have only been a looser for about 2-3 years of my 8 here hence why I have 6k+ :laugh:



Just to stay on topic - drilled & slotted rotors on our cars and 95% of any street car don't do :censored: but make your wallet feel lighter.
 
Rara said:
First, any tests I've been involved with are proprietary, and can't be posted for legal reasons. Second, I said minimal gains because there are very few specific rotor applications where there are improvements. GM put out an SAE paper a few years with some testing on some Corvette rotors that showed an improvement in cooling coefficient, but the paper was very vague about the specifics of what was done, and whether the rotors were even of the same design or not. And there are a few other high-end applications where the design work has been done to utilize the holes to improve airflow rather than hurt it.
Third, and most important, even in cases where improvements are possible, you won't see any evidence of it in normal street driving.

And finally, WTF does what people change on thier cars in the aftermarket have to do with the performance? People put larger wheels on because they look good, but the heavier weight, and increased polar moment of inertia means the car accelerates and brakes worse than stock. People buy new tires, and most of the time get a less grippy tire, because its hard to find a DOT tire that is more grippy than the OEM BFG KDW that came on the CSVT toward the end. People put gigantic wings on the back of thier cars that do nothing but hurt performance. People change out stuff on their cars for all sorts of reasons, and appearance is a HUGE one of those reasons.

The bottom line is that you won't find a contour rotor that performs better when drilled compared to the same rotor without holes, and said drilled rotor will crack and fail significantly quicker than either a plain faced or slotted rotor.
Click to expand...

Ok I think I finally understand the point you were making. In normal Street driving any benefit is purely cosmetic,but when autocrossing or tracking the car the gains are minimal but still there.Am I correct?
 
Maybe instaed of all these personal opinions and hearsay,at the next nationals actually perform a braking shootout. That way the parties involved will actually form concrete evidence to support or sink these theories?
 
SVTDEMON said:
Maybe instaed of all these personal opinions and hearsay,at the next nationals actually perform a braking shootout. That way the parties involved will actually form concrete evidence to support or sink these theories?
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The problem is the person you are arguing with the most is a brake engineer for Ford who also happens to work on a race team. There's no hearsay there.
 
Rara said:
If you don't believe me, a guy with quite a bit of experience designing and developing brake parts for an OEM, and working with a championship winning pro road race team, maybe our resident engineer from Brembo will chime in too.
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LOL, nothing I add will change his closeminded view.

hetfield said:
The problem is the person you are arguing with the most is a brake engineer for Ford who also happens to work on a race team. There's no hearsay there.
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He used to be a brake engineer for Ford (a damn good one too), we both were. Now he is at TRW and the racing gig. I am the lead for brake development at Brembo North America. But like I said, no one will change his mind.
 
I'd be happy to sell you drilled rotors for track day use. The gains are huge!

Don't let these guys talk you out of what I know to be fact: your buying drilled rotors from me for racing will net a huge gain in my wallet. And I'm down for that.
 
Todd TCE said:
I'd be happy to sell you drilled rotors for track day use. The gains are huge!

Don't let these guys talk you out of what I know to be fact: your buying drilled rotors from me for racing will net a huge gain in my wallet. And I'm down for that.
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OMG that made me LOL.... god I feel sick.
 
hetfield said:
The problem is the person you are arguing with the most is a brake engineer for Ford who also happens to work on a race team. There's no hearsay there.
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That is just part of problem is if we haven't attempted to even study this ,then we should take every oppurtunity to advance as group.
 
SVTDEMON said:
That is just part of problem is if we haven't attempted to even study this ,then we should take every oppurtunity to advance as group.
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Just a note... you arent really advancing anything by studying something that is known to be fact. You have several engineers giving you this information, and they have gotten their information from millions of man hours of computation, study, and documentation. Even without them, there are basic physics here that aren't going to change.
 
SVTDEMON said:
Ok I think I finally understand the point you were making. In normal Street driving any benefit is purely cosmetic,but when autocrossing or tracking the car the gains are minimal but still there.Am I correct?
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Not quite.

Normal street driving = only cosmetic.

Autox = only cosmetic.

Open tracking = only cosmetic except for very few and very specific applications that have been engineered to use the holes to improve the bulk airflow, rather than hurt it, like most applications. Generally, there are no minimal gains, but losses if anything.

Racing = same as open track, but even less bother with the effort of doing the holes right, because it just isn't worth it.
 
Silver Snake said:
LOL, nothing I add will change his closeminded view.

He used to be a brake engineer for Ford (a damn good one too), we both were. Now he is at TRW and the racing gig. I am the lead for brake development at Brembo North America. But like I said, no one will change his mind.
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Yeah, I know, but it really bothers me to leave misinformation stand.
 
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