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Oh my God, you people are unbelievable. So who's got the smaller and faster sports car?  
All of this could have been avoided (but at the expense of a really good discussion about thermal temps for rotors) if Rara would have pointed out that Hector saw a marked improvement because it was a performance rotor over an OEM. Unless I am missing the point here as well (it's been known to happen from time to time). Hector also mentioned that the bigger rotor would have been a better idea if you are going to go c/d. Great suggestion to do the experiment with solid vs. c/d under the same conditions, but we know the answer to that already due to this thread and previous threads in this forum. As for Hector spreading BS..well not really. There are many many people spreading BS and he is talking c/d for street conditions and his experience--not saying go out and buy some. Rara has already stated that they should not be used for racing, and from what I gathered are mainly for looks on street cars. MFE, no one has let the issue go so you're a pot calling a kettle black on an "internet board."  It's hard to take a joke, though, when you get beat up on sometimes, ya know. No one likes to be called "dumb". "Dumb" is not productive in a conversation filled with really good information. Combine that with what happens when you attack people on the board and the thread goes to sh*t and all the good info is overlooked because of the name calling and bickering about who said what. 
Rara, Paul, Sleeper, some really good information about rotors. I have been talking about this with a guy from work, and now have something to contribute to that conversation for next week. My .02 has been brought to you by the letters "P" and the letter "W" Carry on...
Mighty Mouse strikes again
Last edited by LoCoChick'95; 05/24/03 01:41 AM.
'95 GL White
I've got mods.
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Hard-core CEG'er
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Hard-core CEG'er
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Originally posted by Paul Kienitz:
Originally posted by RogerB:
1) Learn critical thinking.
2) Learn about the scientific method.
From all appearances, it certainly seems that you are attributing the results to the holes.
"Critical thinking"... my god.
Rara has emphasized that he does brakes for a living, and naturally for someone in that position it's painful to see what seems to be misinformation. Well, I do logic for a living. And seeing misuses of logic like this -- insisting someone is clinging to a given idea even though (a) none of his words actually say so and (b) he's explicitly disavowed the idea being attributed to him... well, that gives me a pain in the same part of my being that hurts Rara if someone thinks cadmium plating shortens stopping distances.
This reminds me of an email debate I got into over the war in Iraq. The other guy kept coming back to an idea that I must hate America. I don't, of course, yet no matter how much I explain that I object to only to certain specific policies, he still thinks it's all proof that I hate America. It was like having someone constantly insist that you must be gay when you know you're not. We can avoid this kind of crap if we just grant the other party the basic respect of assuming that he knows what his own position is, and if he says it's X, then it's X, and it's not your place to claim he really must have meant Y.
You forgot to read this part of my quote:
Quote:
If you weren't then you would say something like, "My stock replacements warped, but my KVR's didn't." Instead, you stress over and over how they are crossdrilled. Language is a funny thing.
Sure enough, he says C/D over and over and over. If he didn't mean that, well, then he shouldn't have said it. And he hasn't disavowed it. He has said "It's just my opinion." Or, he has said things like, "I never said that."
I do logic for a living, too, and I must say that comparing a technical disagreement to a political disagreement is pretty pathetic in the relevant analogy department.
Now, if Hector understood critical thinking, he would never say half the crap he has said about how great crossdrilling is (despite all evidence to the contrary.) If he has changed his mind, great. If not, so what. You can't save everyone.
Oh, I've read the whole thread, BTW, but as I said, I really don't recall any "disavowal" by Hector. If you care to present it, I will readily admit my error. That's called honor. Something else that seems in short supply these days.
Function before fashion.
'96 Contour SE
"Toss the Contour into a corner, and it's as easy to catch as a softball thrown by a preschooler." -Edmunds, 1998
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Since I easily loose arguments with myself, all I like to add is thanks to RogerB for sharing the URL's. The Stop Tech's articles has cleared up allot of myths I've heard over the years. A now retired engineer once told me, he never would comment on any technical issue that he himself hadn't run tests/R & D. And one other scarey issue, the more I learn the more I realize I don't know. i.e. "always keep an open mind" TNX Paul holes is current flow---right? 
Paul
98 Mystique LS 2ea (07/97)(08/98)
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Hard-core CEG'er
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Originally posted by F111D F:
Since I easily loose arguments with myself, all I like to add is thanks to RogerB for sharing the URL's. The Stop Tech's articles has cleared up allot of myths I've heard over the years.
A now retired engineer once told me, he never would comment on any technical issue that he himself hadn't run tests/R & D.
And one other scarey issue, the more I learn the more I realize I don't know. i.e. "always keep an open mind"
TNX
Paul
holes is current flow---right?
It's good that someone got something out of this thread. I thought the bickering here was a waste of bandwidth. Maybe it wasn't after all.
Jim Johnson
98 SVT
03 Escape Limited
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Addicted CEG\'er
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This is the biggest flame fest I have ever seen!!! At least the stoptech articles made it in. . . .
#4559 of 6535 born on Feb 17, 1998
Black 1998.5 CSVT
FOR SALE [cleaning house]: SVT rear swaybar. Reasonable offer and its yours!
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"Absolut Rara."
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"Absolut Rara."
Joined: Sep 2000
Posts: 3,223 |
Originally posted by Kingpin:
This is the biggest flame fest I have ever seen!!! At least the stoptech articles made it in. . . .
You're kidding right? Very very little flaming going on here. What you see is a warm technical discussion.
I can't stand the "why can't we all just get along" sentiment; I stand firm in the old school "let's hash it out until its right".
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Oh by all means dont get along, I have learned more about brakes than ever in this post. Well at least enough to hold my own when someone starts talking about brakes. And I will say, I have been quite entertained in the process! 
#4559 of 6535 born on Feb 17, 1998
Black 1998.5 CSVT
FOR SALE [cleaning house]: SVT rear swaybar. Reasonable offer and its yours!
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CEG\'er
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CEG\'er
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As long as people are learning it's never a waste of bandwidth. I'm glad to see that logic rears it's head. Often times it gets pushed aside in the rush to "upgrade" our cars.
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New CEG\'er
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Originally posted by MFE:
Brakes work by converting kinetic energy to heat energy through the use of friction.
The more heat energy the rotors can accept, the more braking power you have.
Cross-drilling reduces mass more than they add cooling capacity thanks to the holes.
Reduced mass means reduced heat sink.
Reduced heat sink means the rotors can't accept as much heat energy. Therefore reduced braking power is the result.
Actually once brakes have absorbed heat from the initial braking, the ability to transfer thermal energy away from the brake to the air becomes the limiting factor. The heat capacity of the rotor becomes a minor effect.
Properly designed hollow rotors have more than twice the radiating area of solid disc rotors. This has resulted in the trend toward hollow vented rotors in the past decade despite increased manufacturing difficulties and costs.
Cross drilling and slotting of rotors is a doubled edged sword. Most of the problems with rotor cracking with drilled rotors relate to the quality of the drilling or machining job.
If the cross drilling is done in a manner where problems are created in the rotor, then cracking may occur. Problems include:
1/ the holes intersect cross webs,
2/ excess heat is generated from too fast of a machining process or lack of a cooling fluid during drilling,
3/ stress is trapped in the rotor and distortion occurs from excessively fast drilling,
4/ microcracks form during a poorly controlled drilling process, or
5/ sharp edges are left at the hole corners that lead to stress cracks. After drilling the corners should be radiused or chamfered to remove sharp corners.
If any of the conditions above happen it would not surprise me if rotor cracking occurs.
At the other extreme, rotors made from quality materials can be machined using best practices, annealed after machining and a light cut taken on the wear surfaces. I would expect cracking of these rotors to happen with a very small occurance rate.
If you know what you are doing you can carefully machine the surface of drilled and slotted rotors, chamfer the corners and avoid problems.
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All this sounds great. Now show me the shop or machine that radius's the holes after they are drilled. Oh, not the outside of the hole, we see that part, but rather the INSIDE of the hole where the venting or vanes are.
Your comments are valid in many ways, but drill a cast iron rotor and subject it to abuse equal to that of an undrilled one and it'll crack much sooner.
For you guys with them, just keep and eye on the holes once in a while and replace them. That's all is needed. Wait for large cracks and it's trouble.
Bottom line: buy what floats your boat and live with it.
Last edited by Todd TCE; 05/31/03 12:00 AM.
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