help me settle this debate
08-30-2009, 07:11 PM
#42
I just got back from VIR yesterday. I have been there over 10 times. I am not the fastest driver and I have never . . . and I mean never, ever, not even close, been even threatened by a miata, stock, raced prepped or whatever. Don't see why you should. It blows me away when I see them run off track cause I don't see how they get enough speed to do it. You should upgrade your fluid and pads and you will be fine.
As for the drilled/slotted debate, if you look at what people who pay for their own stuff bring to the track, it is mostly stock rotors. Some run the slotted as it does help in braking, but it also eats thru pads quickly. That being said, I run the drilled/slotted when I am on the street, but at the track, I switch to stock rotors I buy from people switching to d/s.
BTW - VIR is an awesome track, you should start running there whenever possible. Good Luck.
As for the drilled/slotted debate, if you look at what people who pay for their own stuff bring to the track, it is mostly stock rotors. Some run the slotted as it does help in braking, but it also eats thru pads quickly. That being said, I run the drilled/slotted when I am on the street, but at the track, I switch to stock rotors I buy from people switching to d/s.
BTW - VIR is an awesome track, you should start running there whenever possible. Good Luck.
09-18-2009, 10:50 AM
#43
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I'm sure some of them don't use them, everyone has there own preferrances. I'm just saying all that I have seen in the 15+ years I have been working around race cars (not just a random fan with a pit pass) all have used them. My point was that alot of people act like they provide a disadvantage in braking performance, that is what I wanted to find out. If they don't stop as well as blanks, why are they used by anybody? Even alot of high end street cars come stock with drilled and/or slotted rotors. I seriously want to know if someone could give me facts (or a link if its easier) because I'm in the market for a new setup and I don't want junk on my car! As far as cracks, do they completely break apart, or are they just fine cracks like all rotors tend to get with age?
After that longwinded paragraph, I want to answer your question about why all of the high-dollar exotics run cross-drilled rotors and don't seem to have problems. Most likely, those rotors are so expensive that they were actually cast with the holes in them. They did not start out as blanks and then had the holes drilled, which significantly weakens the area around the holes, hence the heat cracking that extends from the drill holes radially. Those expensive rotors, with the holes cast in them from the start, can reduce rotating mass at the wheels, which can have a big impact on how much horsepower is getting put to the ground, handling, braking, etc. All the things that exotics must do well.
It was touched on before, but I believe that a lot of racecars run the drilled and slotted (or slotted only) because each individual rotor will only last for a certain amount of laps (or 1 race - depending on the length) and will be thrown away before any of those cracking problems would typically ever occur. And they probably get those rotors from a very high quality source to ensure that the metal is up to the task of absorbing massive amounts of heat (through friction) time after time.
I hope this helps. Just so you know, I am no expert on street cars or racecars, I have just done a lot of reading and researching on the subject and I am a Civil Engineer so I have at least a rudimentary knowledge of physics, heat transfer, mechanics of materials, etc. which all play into high performance braking.
09-18-2009, 01:23 PM
#45
Most every road race car will use slotted rotors. VERY few today use a drilled rotor.
Slotting helps clear dust away and can lessen the grooving and scoring that happens when dirt and dust get embedded in a pad, I have see the improvement directly. The other thing is race cars generally build much more brake temperature than street cars do. And big cars like IndyCars, ALMS, Grand-Am cars don't have power brakes. The slotting helps to get rid of the gas layer that can build @ 1000 degrees and act as a buffer between the pad and rotor. Slotting helps get the gases out. If you have power brakes, you have a much easier time getting through that gas.
The toughest rotors I've found for stock sized LS1 brakes are the Racing Brake stuff. I picked them up because they are the most durable and run the coolest for track use. In fact the Racing Brake fronts use convergent, and directional vanes on the front... the only LS1 rotor that does. They are also made of a metal composition that is a lot tougher than street rotors. And fwiw, they also cost more because it requires more tooling because they are making two different rotors, one for each side where others cheap out and make one rotor that works for both sides (like GM). That's fine for street use, even some fairly hard street use--but not ideal when you are really pounding on the brakes like at a track day.
Slotting helps clear dust away and can lessen the grooving and scoring that happens when dirt and dust get embedded in a pad, I have see the improvement directly. The other thing is race cars generally build much more brake temperature than street cars do. And big cars like IndyCars, ALMS, Grand-Am cars don't have power brakes. The slotting helps to get rid of the gas layer that can build @ 1000 degrees and act as a buffer between the pad and rotor. Slotting helps get the gases out. If you have power brakes, you have a much easier time getting through that gas.
The toughest rotors I've found for stock sized LS1 brakes are the Racing Brake stuff. I picked them up because they are the most durable and run the coolest for track use. In fact the Racing Brake fronts use convergent, and directional vanes on the front... the only LS1 rotor that does. They are also made of a metal composition that is a lot tougher than street rotors. And fwiw, they also cost more because it requires more tooling because they are making two different rotors, one for each side where others cheap out and make one rotor that works for both sides (like GM). That's fine for street use, even some fairly hard street use--but not ideal when you are really pounding on the brakes like at a track day.
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Results matter. Talk is cheap. We are miles beyond the success anyone else has had with the 4th gens, and C5, C6, C7 Corvettes,
10 SCCA Solo National Championships, 2008 Driver of they Year, 2012 Driver of Eminence
13 SCCA Pro Solo Nationals Championships
2023 UMI King of the Mountain Champion
09-18-2009, 07:57 PM
#46
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Well...if you had read the post above yours 
, you would have seen that the reason drilled rotors exist, and especially on expensive exotic cars, is two-fold. One, they look cool, and two (the bigger reason) they actually make the rotor lighter, therefore reducing unsprung (or rotational mass). Even to shave 1 pound total off of the 4 rotors is something that exotic car manufacturers like to do. That may seem trivial to a layperson, but even small amounts of weight being removed from the wheel, caliper, caliper bolts, rotors, etc. have a relatively big increase in performance over say...changing the front seats to lighter racing seats and saving 80 lbs from the sprung weight of the car.
I believe that this is the same reason that the highest dollar brakes out there utilize ceramic rotors because they are much lighter (see above about lowering rotating mass) and have a superior ability to dissipate high amounts of heat.
By the way, I do agree with you as far as not taking that risk in track applications, but street cars (albeit highend ones) were also brought into the mix, and d/s rotors can perform great on the street.
Also something I just thought of, is I have seen an awful lot of late model Porsches that have those drilled-only rotors and I am betting that those are the types that are cast with the holes in them. I don't know about everybody's experience, but every time I have ever been to a track day I have seen some type of Porsche. And I think that a majority of guys that own Porsches like to track them, and I have never heard of their rotors cracking, warping, or breaking while on the track, so apparently Porsche has the whole drilled thing figured out.
, you would have seen that the reason drilled rotors exist, and especially on expensive exotic cars, is two-fold. One, they look cool, and two (the bigger reason) they actually make the rotor lighter, therefore reducing unsprung (or rotational mass). Even to shave 1 pound total off of the 4 rotors is something that exotic car manufacturers like to do. That may seem trivial to a layperson, but even small amounts of weight being removed from the wheel, caliper, caliper bolts, rotors, etc. have a relatively big increase in performance over say...changing the front seats to lighter racing seats and saving 80 lbs from the sprung weight of the car.I believe that this is the same reason that the highest dollar brakes out there utilize ceramic rotors because they are much lighter (see above about lowering rotating mass) and have a superior ability to dissipate high amounts of heat.
By the way, I do agree with you as far as not taking that risk in track applications, but street cars (albeit highend ones) were also brought into the mix, and d/s rotors can perform great on the street.
Also something I just thought of, is I have seen an awful lot of late model Porsches that have those drilled-only rotors and I am betting that those are the types that are cast with the holes in them. I don't know about everybody's experience, but every time I have ever been to a track day I have seen some type of Porsche. And I think that a majority of guys that own Porsches like to track them, and I have never heard of their rotors cracking, warping, or breaking while on the track, so apparently Porsche has the whole drilled thing figured out.
Last edited by tweeter81; 09-18-2009 at 08:08 PM.
10-02-2009, 10:19 AM
#48
I have a prepped Autocross car. 1994 Formula. It's taken a LOT to get it to run with a stock Miata on a tight course. On an open course with some breathing room I suck them in but they can sometimes still have an advantage in certain locations and will make up the room. I will tell you however that TIRES make a huge difference and without knowing all the details of both cars its hard to judge. Miata's are pretty damn sweet when it comes to a road racing car. They are cheap to mod and race unlike my F-body which is costing a mint. BTW: A Z06 would certainly have NO issues with a stock Miata in any circumstances.
10-02-2009, 01:54 PM
#49
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A couple of things.
First of all, NO ONE drills holes to "lighten" a brake rotor. You want the biggest, heaviest rotor that will stop the car. All that mass absorbs heat, which yields better braking. However, once you have a rotor that's big enough, you want all that mass as close to the hub as possible. My point here is that, why drill holes, which remove mass near the hub but leave it out near the wheel, when you could make the rotor smaller in diameter, have the same braking performance, but reduce moments of interia?
Second, yes, drilled crack a little worse than cast holes. But, all holes crack. Why? Because that are of the rotor will cool faster than the undrilled parts next to it. As it cools, it shrinks. As it shrinks, it pulls away from the surrounding metal. If that force is stronger than the forces holding the metal together, a crack will form.
Lastly, some real-world experience. I have 14" Baer 2-piece rotors, with stock-style Corvette calipers. When I bought the brakes, they came with slotted and drilled rotors. They were fine for braking. However, after only 3 race (20 minutes apiece) the cracks at the holes had grown from imperceptable to connecting holes and extending to the edge of the rotor.
Now, I have baer blanks. They've lasted 6 races, and look brand new. Braking performance is roughly the same. But, at $200 per rotor, it's a helluva lot cheaper!
First of all, NO ONE drills holes to "lighten" a brake rotor. You want the biggest, heaviest rotor that will stop the car. All that mass absorbs heat, which yields better braking. However, once you have a rotor that's big enough, you want all that mass as close to the hub as possible. My point here is that, why drill holes, which remove mass near the hub but leave it out near the wheel, when you could make the rotor smaller in diameter, have the same braking performance, but reduce moments of interia?
Second, yes, drilled crack a little worse than cast holes. But, all holes crack. Why? Because that are of the rotor will cool faster than the undrilled parts next to it. As it cools, it shrinks. As it shrinks, it pulls away from the surrounding metal. If that force is stronger than the forces holding the metal together, a crack will form.
Lastly, some real-world experience. I have 14" Baer 2-piece rotors, with stock-style Corvette calipers. When I bought the brakes, they came with slotted and drilled rotors. They were fine for braking. However, after only 3 race (20 minutes apiece) the cracks at the holes had grown from imperceptable to connecting holes and extending to the edge of the rotor.
Now, I have baer blanks. They've lasted 6 races, and look brand new. Braking performance is roughly the same. But, at $200 per rotor, it's a helluva lot cheaper!
10-02-2009, 02:30 PM
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here is the layout of the track. 3.27 miles long with a 3000 ft front straightaway and a 4000 ft back straightaway. I just dont think there is no way in hell a stock miata can stay far enough ahead of me in the turns that i couldnt make up on the straights.fortunately this track favors HP...BUT, the corners are slow and difficult. For a first timer like I believe you would (I may be wrong..) be, I bet a "Pro" Miata driver could easily keep pace with you and with real race experience get by you no problem...not to say you may not be able to catch up with him on the straights, but it all depends on how quickly you learn and catch on. The race track is no place to be a hero when you are beginner, that gets you into trouble.
Now, what kind of "Pro" are we talking here? Does he have a full paid ride with sponsors and a team that covers ALL of his expenses and he makes $$ off it, or is he a "Pro" driver who has a couple/few sponsors who help out on tires or brake pads or race entries and a team of him and a couple friends and is still out $$ at the end of weekend?
Because there are 2 different level of "Pro" drivers out there, those who can afford to be called a "Pro", and those who are that talented of drivers..
10-02-2009, 02:33 PM
#51
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oh, and depending on driving styles/braking habits and setups....more specifically stock rotors, inadequate cooling, stock calipers, and race pads; slotted rotors can help resurface the pads helping to prevent the over-heating and thus creating pad glazing during a session.
Ask how I know this... :o
Ask how I know this... :o
10-03-2009, 07:48 PM
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A couple of things.
First of all, NO ONE drills holes to "lighten" a brake rotor. You want the biggest, heaviest rotor that will stop the car. All that mass absorbs heat, which yields better braking. However, once you have a rotor that's big enough, you want all that mass as close to the hub as possible. My point here is that, why drill holes, which remove mass near the hub but leave it out near the wheel, when you could make the rotor smaller in diameter, have the same braking performance, but reduce moments of interia?
Second, yes, drilled crack a little worse than cast holes. But, all holes crack. Why? Because that are of the rotor will cool faster than the undrilled parts next to it. As it cools, it shrinks. As it shrinks, it pulls away from the surrounding metal. If that force is stronger than the forces holding the metal together, a crack will form.
Lastly, some real-world experience. I have 14" Baer 2-piece rotors, with stock-style Corvette calipers. When I bought the brakes, they came with slotted and drilled rotors. They were fine for braking. However, after only 3 race (20 minutes apiece) the cracks at the holes had grown from imperceptable to connecting holes and extending to the edge of the rotor.
Now, I have baer blanks. They've lasted 6 races, and look brand new. Braking performance is roughly the same. But, at $200 per rotor, it's a helluva lot cheaper!
First of all, NO ONE drills holes to "lighten" a brake rotor. You want the biggest, heaviest rotor that will stop the car. All that mass absorbs heat, which yields better braking. However, once you have a rotor that's big enough, you want all that mass as close to the hub as possible. My point here is that, why drill holes, which remove mass near the hub but leave it out near the wheel, when you could make the rotor smaller in diameter, have the same braking performance, but reduce moments of interia?
Second, yes, drilled crack a little worse than cast holes. But, all holes crack. Why? Because that are of the rotor will cool faster than the undrilled parts next to it. As it cools, it shrinks. As it shrinks, it pulls away from the surrounding metal. If that force is stronger than the forces holding the metal together, a crack will form.
Lastly, some real-world experience. I have 14" Baer 2-piece rotors, with stock-style Corvette calipers. When I bought the brakes, they came with slotted and drilled rotors. They were fine for braking. However, after only 3 race (20 minutes apiece) the cracks at the holes had grown from imperceptable to connecting holes and extending to the edge of the rotor.
Now, I have baer blanks. They've lasted 6 races, and look brand new. Braking performance is roughly the same. But, at $200 per rotor, it's a helluva lot cheaper!
) and see if your braking performance increases or decreases. Good braking also has to do with how much weight (mass x gravity) you are stopping, and in the case of rotational mass, every little bit saved really helps.As for your argument about the area of the rotor near the holes cracking because it cools faster, I agree with you that it does cool faster by a small amount, but I don't think that is enough to make a rotor (with pre-cast holes) break. Again, by your logic, why wouldn't the extreme outside edge of all rotors crack and "pull away" from the other metal because that particular area cools slightly faster than the rest of the rotor. It doesn't happen...
The cracking around the holes of all rotors that have been drilled after the fact is from the stresses put on the metal through the drilling process, which are then exacerbated during the repeated heating and cooling process when used on the track.
10-13-2009, 06:57 PM
#53
Wow, lots of good info here! Thanks for the insight guys! Hopefully it will help me out pretty soon. I'm also heading to VIR to turn some laps. I'm gonna have an instructor with me though. I'm pretty confident in my driving, but it never hurts to have a pro show you the ropes!
10-14-2009, 12:34 PM
#54
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Also the mass of a rotor has nothing to do with the heat dissipating abilities of said rotor.
Now, it is true that a lighter rotor will also cool faster. But, if you've already glazed your pads because you exceeded their heat range, then what's the point?
The surface contact of the brake pad on the rotor surface is what determines the loss of forward momentum via friction heat losses. Why would highly paid, extremely intelligent design engineers use the very light ceramic or even carbon fiber rotors (look it up to believe it, I did) on a supercar or racecar?
Obviously by your logic they wouldn't work for crap because that aren't the "biggest, heaviest rotors" you could fit under the wheels...which is not true at all. I dare you to go out and find a couple of 100 lb rotors and bolt those up to your car (it must work better because it has so much mass...) and see if your braking performance increases or decreases.
) and see if your braking performance increases or decreases. Notice I said "biggest, heaviest that will stop the car"? Once your brakes will stop the car like you want, then there is no reason to get bigger/heavier brakes. That limit is usually found by when your tires lockup. Once you ahve locked up the tires, there is no reason to have better brakes. If there is no reason to have better brakes, then there is no reason to have heavier brakes.
As for your argument about the area of the rotor near the holes cracking because it cools faster, I agree with you that it does cool faster by a small amount, but I don't think that is enough to make a rotor (with pre-cast holes) break. Again, by your logic, why wouldn't the extreme outside edge of all rotors crack and "pull away" from the other metal because that particular area cools slightly faster than the rest of the rotor. It doesn't happen...
The cracking around the holes of all rotors that have been drilled after the fact is from the stresses put on the metal through the drilling process, which are then exacerbated during the repeated heating and cooling process when used on the track.
Originally Posted by http://www.cryogenicsinternational.com/rotors.htm
Some drilled holes in rotors are not really drilled at all. They are cast holes. This is done to help minimize the effects a hole has in creating a stress riser in the surface of the brake rotor. A drilled hole goes directly through and interrupts the grain structure of the metal. Where a cast hole has the grain structure formed around it in an uninterrupted flow. All holes in a brake rotor will eventually show signs of stress cracking. A drilled hole will crack much sooner than a cast one. Admittedly, a “drilled” rotor will cool better than a smooth rotor, and has slightly better “bite”. However, the person who blindly goes ahead and drills his stock rotors is asking for trouble, especially in high heat or severe brake conditions. It’s not unusual for these rotors to eventually crack completely across the surface, causing a dangerous situation. Therefore, it is not recommended to drill unless it is for an under-stressed condition or, for a street car just for looks. The best solution for people who want maximum life and safety out of their rotors, is to have standard or slotted rotors deep cryogenically treated.
Of course, if you have the money to buy new rotors and pads after every race ($200/rotor, $300 for front pads = $700/race), then you should probably spend $9k on a set of ceramic brakes. It'll be worth it in terms of performancea AND economics.
10-27-2009, 10:55 AM
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People who are trying to sell a product will "market" them in whatever way they think will sell the most product. Just because they say something doesn't mean that it's true.
I agree with that, but the point I am trying to make is that obviously a lot of car designers/mechanical engineers feel like there is some merit in cross-drilled rotors. Case in point, have you seen the new McLaren MP4-12C? That car (and all McLarens) are the hardest of the hardcore, and the brand new design has cross-drilled rotors. I think that the McLaren Engineers must be on to something. I mean, they only built the BEST sports car in the world with the McLaren F1 (over 10 years ago).
Of course it does. What takes longer to heat up if you use a cigarette lighter - a paperclip or a steel I-beam? A lighter rotor will heat up faster, and therefore heat up more. Therefore, it will hit a higher heat point, which is likely to exceed the rating of the pads used.
Good point, but all of the relatively cheap rotors that we are discussing are made from the same material, cast iron, which is going to absorb a set amount of heat at a set rate. I am not a Chemistry genius, but just because a lighter rotor might heat up faster, absolutely does not mean it will heat up more, there are many other factors that would determine the maximum amount of heat that a rotor could absorb and store.
I think the differences in mass of a cross-drilled rotor to a blank rotor are fairly small (although, like I said before, even shaving 1/4 lb to 1/2 lb off of a rotor is pretty big for performance gains and track times on a roadcourse...you should know that being a track guy) and I also think the amount of heat (friction) absorbed would be almost indistinguishable between the two types of rotors. What I am saying is, for my money, I would rather have more efficient rotors that are somewhat lighter than a regular blank, because you are fighting the weight of the rotor 100% of the time due to physics, but you are only using the brakes a smaller percentage of the time.
Now, it is true that a lighter rotor will also cool faster. But, if you've already glazed your pads because you exceeded their heat range, then what's the point?
Then you need better pads...
You can't compare "why/how" a ceramic/CF rotor works to "why/how" a ferrous-metal rotor works. An iron rotor with regular pads works by combining 2 methods to stop the car - converting momentum to heat and friction. That's why you get brake dust, you have to replace race pads every few races, and have to get new rotors. But, ceramic/CF rotors don't use the "friction" part of that. Movit brakes has a ceramic rotor/pad combo that has been on their dyno for years now, and has logged a few hundred thousand miles of simulated racetrack driving. They are still on the original pad and rotor. They simply don't wear out.
Obviously you know more about that than I do, so I won't argue the info.
Sure, let's take it to extremes - that's a valid arguement.
I only took it to extremes because of your comment, see below...
Notice I said "biggest, heaviest that will stop the car"? Once your brakes will stop the car like you want, then there is no reason to get bigger/heavier brakes. That limit is usually found by when your tires lockup. Once you ahve locked up the tires, there is no reason to have better brakes. If there is no reason to have better brakes, then there is no reason to have heavier brakes.
That is pretty sound logic, again I can't argue about this point.
Ummm - because it's a circle. As the outside of the rotor cools, it tries to get smaller. This means that it actually draws CLOSER to the metal on the inside of the rotor.
Well, you have an inconsistency in your statements then. I agree that the metal contracts as it cools, so it would also stand to reason that the metal at the edge of the drill holes would contract into the rest of the rotor, not pull away from it like you said before.
So, unless you have the funds to buy new rotors after every or every other race, then you should get slotted or blank rotors.
Of course, if you have the money to buy new rotors and pads after every race ($200/rotor, $300 for front pads = $700/race), then you should probably spend $9k on a set of ceramic brakes. It'll be worth it in terms of performancea AND economics.
Very true.
I agree with that, but the point I am trying to make is that obviously a lot of car designers/mechanical engineers feel like there is some merit in cross-drilled rotors. Case in point, have you seen the new McLaren MP4-12C? That car (and all McLarens) are the hardest of the hardcore, and the brand new design has cross-drilled rotors. I think that the McLaren Engineers must be on to something. I mean, they only built the BEST sports car in the world with the McLaren F1 (over 10 years ago).
Of course it does. What takes longer to heat up if you use a cigarette lighter - a paperclip or a steel I-beam? A lighter rotor will heat up faster, and therefore heat up more. Therefore, it will hit a higher heat point, which is likely to exceed the rating of the pads used.
Good point, but all of the relatively cheap rotors that we are discussing are made from the same material, cast iron, which is going to absorb a set amount of heat at a set rate. I am not a Chemistry genius, but just because a lighter rotor might heat up faster, absolutely does not mean it will heat up more, there are many other factors that would determine the maximum amount of heat that a rotor could absorb and store.
I think the differences in mass of a cross-drilled rotor to a blank rotor are fairly small (although, like I said before, even shaving 1/4 lb to 1/2 lb off of a rotor is pretty big for performance gains and track times on a roadcourse...you should know that being a track guy) and I also think the amount of heat (friction) absorbed would be almost indistinguishable between the two types of rotors. What I am saying is, for my money, I would rather have more efficient rotors that are somewhat lighter than a regular blank, because you are fighting the weight of the rotor 100% of the time due to physics, but you are only using the brakes a smaller percentage of the time.
Now, it is true that a lighter rotor will also cool faster. But, if you've already glazed your pads because you exceeded their heat range, then what's the point?
Then you need better pads...
You can't compare "why/how" a ceramic/CF rotor works to "why/how" a ferrous-metal rotor works. An iron rotor with regular pads works by combining 2 methods to stop the car - converting momentum to heat and friction. That's why you get brake dust, you have to replace race pads every few races, and have to get new rotors. But, ceramic/CF rotors don't use the "friction" part of that. Movit brakes has a ceramic rotor/pad combo that has been on their dyno for years now, and has logged a few hundred thousand miles of simulated racetrack driving. They are still on the original pad and rotor. They simply don't wear out.
Obviously you know more about that than I do, so I won't argue the info.
Sure, let's take it to extremes - that's a valid arguement.
I only took it to extremes because of your comment, see below...
Notice I said "biggest, heaviest that will stop the car"? Once your brakes will stop the car like you want, then there is no reason to get bigger/heavier brakes. That limit is usually found by when your tires lockup. Once you ahve locked up the tires, there is no reason to have better brakes. If there is no reason to have better brakes, then there is no reason to have heavier brakes.
That is pretty sound logic, again I can't argue about this point.
Ummm - because it's a circle. As the outside of the rotor cools, it tries to get smaller. This means that it actually draws CLOSER to the metal on the inside of the rotor.
Well, you have an inconsistency in your statements then. I agree that the metal contracts as it cools, so it would also stand to reason that the metal at the edge of the drill holes would contract into the rest of the rotor, not pull away from it like you said before.
So, unless you have the funds to buy new rotors after every or every other race, then you should get slotted or blank rotors.
Of course, if you have the money to buy new rotors and pads after every race ($200/rotor, $300 for front pads = $700/race), then you should probably spend $9k on a set of ceramic brakes. It'll be worth it in terms of performancea AND economics.
Very true.
Last edited by tweeter81; 10-28-2009 at 07:35 PM.
10-27-2009, 12:06 PM
#56
Originally Posted by 00 Trans Ram
People who are trying to sell a product will "market" them in whatever way they think will sell the most product. Just because they say something doesn't mean that it's true.
I agree with that, but the point I am trying to make is that obviously a lot of car designers/mechanical engineers feel like there is some merit in cross-drilled rotors. Case in point, have you seen the new McLaren MP4-12C? That car (and all McLarens) are the hardest of the hardcore, and the brand new design has cross-drilled rotors. I think that the McLaren Engineers must be on to something. I mean, they only built the BEST sports car in the world with the McLaren F1 (over 10 years ago).
People who are trying to sell a product will "market" them in whatever way they think will sell the most product. Just because they say something doesn't mean that it's true.
I agree with that, but the point I am trying to make is that obviously a lot of car designers/mechanical engineers feel like there is some merit in cross-drilled rotors. Case in point, have you seen the new McLaren MP4-12C? That car (and all McLarens) are the hardest of the hardcore, and the brand new design has cross-drilled rotors. I think that the McLaren Engineers must be on to something. I mean, they only built the BEST sports car in the world with the McLaren F1 (over 10 years ago).
... they are made from the same material as teh $100 rotors available from rotorsRus.com
... owners routinely run them on the track and then drive them to work the next day
... because a wing on a McClaren "works", a wing on a Civic must work also because its a wing
... the rotors will last 60K miles, not just a 1 hour race.
10-27-2009, 01:44 PM
#58
Silverbeast,
In stead of coming here & yappin' about it, why not go out & see? Stock Miata's can be rented & I'm sure that there will be pro's @ the track who will put seat time in one for the test. In a 10 lap race (time trial), I'd give it to the pro in the stock Miata. You didn't mention how many laps & also didn't mention that you'd be in here learning how to set up your car before the race. Sounds like your friend offered the statement as "stock Miata" against "your car as it sat in the parking lot on that day." In any event, an inexperienced road course driver over 10 laps against a pro in a lesser car = Pro FTW.
One lap, you might have a chance.
In stead of coming here & yappin' about it, why not go out & see? Stock Miata's can be rented & I'm sure that there will be pro's @ the track who will put seat time in one for the test. In a 10 lap race (time trial), I'd give it to the pro in the stock Miata. You didn't mention how many laps & also didn't mention that you'd be in here learning how to set up your car before the race. Sounds like your friend offered the statement as "stock Miata" against "your car as it sat in the parking lot on that day." In any event, an inexperienced road course driver over 10 laps against a pro in a lesser car = Pro FTW.
One lap, you might have a chance.
10-29-2009, 08:47 AM
#59
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miata vs LSx cars C5/6 vs a miata. 10 seconds or more.
Which is why I am looking for a LSx powered bmw.
I bet a rookie could keep Shumacher (SP?) in a stock miata at bay on that track. However, based on our track, your stock brakes would be done after 3 laps (ask me how I know), so the miata would eventually win, depending on length of laps. Rookies tend to use way more brakes than normal, as they (used to be me too) over brake, and have less body control (adversly affecting braking/speeds/etc) using the tires/engine to brake. I went through 2 sets in the audi in 3 track events. 3800lbs and 340hp is not a good road racing receipie.
In my almost stock 09 subaru 265, I double lapped a girl in a 20 minute session in a mazda speed miata, and a guy in a gutless one (199x). My laps times are about 90 seconds. Faster guys are 85, super fast are 80 seconds. 20 seconds a lap is huge.
Summary, I would be a ton of money on you, but there is no way to find out, but race him. Take a class, practice being smooth, your car will appreciate it. Don't try to beat everything in site. Steady, consistent movements, not herky jerky will get you around fast.