MrHeeltoe

iTrader: (1)

The rotors are made from an alloy that has a higher level of carbon and silicon (among other alloying elements) which makes them harder and more wear resistant (compacted graphite iron, if you must know). Heat treatment alters the chemical structure of the material further hardening it. No this material is not magical and no it does not dissipate heat more than standard grey iron. But it does have the ability to hold more heat, which prevents the rotor from overheating.

The ability to dissipate heat is provided by the aluminum hats and curved vane structure. Heat is sucked from the rotor faces by the hats and dissipated into the wheel, while simultaneously the curved vanes pump air through the cooling channel at a higher volume than standard straight vaned rotors.

If you really believe that "reduced swept area reduces surface area and ability to stop the car" you are more naive than I thought before. The same amount of pressure is applied to the pads and therefore the pads to the rotors. Friction is a function of frictional coefficient (brake pads) and normal force (caliper pressure). You don't lose friction with slotted or drilled rotors. The normal force is simply distributed over a fractionally smaller area, thereby increasing the pressure over that area. You get the same psi with slotted rotors as you do blank ones, and therefore the same friction force with equivalent pads. Please. Go home with that argument. Don't bother linking me to a bunch of other retards out there who think the same thing.

Higher pressure and aggressive pads do increase braking by increasing friction, which does wear the rotor more as well. However Racingbrake rotors, being much harder than standard and 99% of all other competitors, wear at a much slower rate. Expect 2-3 times the life out of them. Without needing to resurface them.

All those cars, while they may have larger rotors, have inferior calipers. Don't forget...calipers and pads stop the car; not rotors. The TL-S brakes are perfectly suited to the car, but not to high performance driving. The idea that Brembo calipers being fitted to the car is somewhat of a marketing ploy to sell more cars is not a new idea...but it does not change the fact that the TL-S stops very well, and the only thing that really would make the brakes better are a set of 2-piece rotors (which are simply too expensive to ever come standard) and steel braided lines, which compromise the comfort level of the car too much to be standard.

Acura cares about unsprung weight just as much as the next company. And if they wanted to make a 4dr NSX (which has aluminum suspension...and body for that matter) they would probably charge a hell of a lot more than $36K or whatever the TL-S costs. You completely missed the point though. Are you actually telling me that you understand the point of reducing unsprung weight, yet you still encourage the increasing of it because you don't think Acura cares about it? That whole comment seemed like a waste of electrons. As is largely every post of yours I have read.

Heh, I like how you assumed that you "de-merited" my post before I had a chance to reply.

harddrivin1le

The stock rotors are vented (fronts) and also have aluminum hats. So the aftermarket stuff has no advantage there.

Swept area is reduced when the rotors are slotted or drilled. That is fact. Swept Area per ton is a widely accepted standard for qualifying braking performance. If nothing else, reduced swept area will increase rotor wear. Slotting and drilling also reduces rotor mass.

Please describe "inferior calipers." They'll stop the car just as well as fancy, 4 piston calipers if the clamping force is the same. 4 piston calipers can, in theory, provide superior feel and better initial response. They do not necessarily increase stopping clamping force or stopping power.

Corvettes (including the Z51s) use "inferior" 2 piston/sliding calipers. Go drive one and see how "bad" the brakes are. They are FANTASTIC. That's because they use LARGE ROTORS.

A larger diameter rotor offers a longer braking moment arm, which provides an immediate and directly proportional mechanical advantage which translates to increased friction horsepower (i.e. stopping power). With the larger rotor comes more mass and greater surface area, which provides for a higher rate of heat dissipation.

Rotors also cool by convection - directly from their flat surface friction surfaces. You left that part out. Greater surface area promotes superior heat dissipation.

Aftermarket rotors of OEM diameter are a waste of money. They are a modern version of "snake oil." The fact that you make a profit by selling them won't change that fact.

The TL-S stops "very well" from one or two cold stops at relatively low speeds, where tires, road surface, weight transfer and ABS algorithms are the dominate variables in most modern cars. The TL-S's braking prowess falls off rapidly once the car is subjected to hard, repeated stops, since the rotors are too small and are therefore unable to effectively dissipate heat.

KeithL

Which Hawk Pads did you get? Do you have th epart numbers? Did you do all around, or just the fronts?

Evader

What's everyones opinon on Rotora Slotted rotors with Hawk HPS Pads?

harddrivin1le

Any rotor that's the same size as the OEMs is a waste of money - regardless what any salesman tells you.

sherwin991

iTrader: (1)

Thanks for the reply, I appreciate it. Guess I'll be calling Marcus now for a price on those pads plus the Racing Brake rotors.

MrHeeltoe

iTrader: (1)

This is simply not correct. The stock rotors are 1-piece cast iron.

Yes it is a fact, but a nominal and semantical one at best. The minuscule ill effect is not noticed and but the degassing and dust shedding benefits of drilling or slotting are greatly noticed. So, your argument, while technically true, is a moot point. You can't tell me that the reduced swept area impacts braking performance to any noticeable degree because it simply doesn't.

Inferior calipers in this case are those with less force-output piston surface area, thereby producing a reduced amount of braking pressure. Of course, I cannot compare the brembo calipers on the TL with those of the other cars mentioned without measuring, but I can compare the TL brembo calipers with base TL calipers. The 4-piston calipers in this case DO provide greater pressure and therefore better braking force.

Don't misunderstand, I did not say the other calipers were inadequite, but they are inferior to brembo monoblock calipers which are more rigid and provide stronger and more direct braking pressure.

The fact that the mentioned cars stop well is due to the fact that the calipers, pads, and rotors are all spec'ed out for performance driving and general track use. The TL-S is not.

I already addressed the torque arm argument. Don't waste anymore time arguing unless you can come up with something new.

The more mass speaks nothing of heat dissipation, just more heat capacity, something I claim that you can attain by simply getting BETTER stock sized rotors. Newsflash, bigger is not always better. In fact the greater rotor mass will actually HOLD the heat more.

Rotors cool by convection, yes, but not just on the rotor face. I can't believe you said that. Heat radiates from the entire rotor surface area, including thermal transfer through the wheel. And there needs to be airflow around all surfaces of the rotor to reduce heat-soak of the surrounding air. By utilizing curved vanes, racingbrake rotors move more air than a conventional rotor thereby increasing the rotor's ability to shed heat.

If you actually have a counterpoint to this that is valid or intelligent, I would be truly surprised.

This statement is not true in all cases. I generally felt the same until racingbrake came out. Nobody can match their construction quality and features. The fact that you cannot comprehend what curved vanes and heat treating set these rotors apart tells me that you really are not engineer of anything.

I agree that increasing rotor size will increase the braking ability of the car, but I strongly suggest getting stock sized rotors of higher quality to achieve the same result at a drastically lower cost.

Marcus

harddrivin1le

I challenge you to produce even one, third party test that depicts an aftermarket rotor of the same size producing markedly better stopping distances than the OEM rotor.
The ONLY variable must be the rotor (e.g. same pads, driver, tires, road surface, etc.) and the information must be third party (i.e. no manufacturer advertising hype).

I also challenge you to prove that the TL-S Brembos provide more clamping force than the standard TL calipers.

Never once did I state that rotors cool by convection "just on the rotor face." I merely pointed out an additional form of heat transfer that you neglected to mention.

harddrivin1le

Get ready to be "surprised:"

http://www.racingbrake.com/main/rotor_vane_design.asp

"Traditional Curved VanesTraditional curved vane: This is the most wildly used design to improve the cooling effect by pumping the cool air from the center of wheel (inboard side only for surface mount design, as opposed to RB's center-mount design which admits cooling air from both inboard and outboard). However, the air inlet from is usually restricted by the dust shield, which essentially has the same cooling effect as one-piece curved vane rotor."

Evader

Marcus, I just sent you an email. I would appreciate if whenever you have a free moment to give me your insight on my questions. This thead is giving me a headache haha

harddrivin1le

Don't buy any OEM size rotor from him (or anyone else) who is unable to produce a valid, 3rd party test proving they outperform the OEM rotor when all other variables (e.g. pads, tires, road surface, driver, temperatures, etc.) are the same.

Evader

So do you have a specific rotor you suggest/promote? I've decided on Hawk pads (not sure which type though, HPS I guess) and I was looking into slotted and/or drilled rotors but don't really know the benefit. This thread seems to have gotten off base and I personally don't find it as informative as the direction it was heading

harddrivin1le

Are your pads ceramics or HPS?

Aftermarket rotors are a waste of money - UNLESS you're willing to pony up the big bucks and buy an entire kit that includes larger rotors with caliper relocation hardware or larger calipers.

Such systems run into big money quickly and generally aren't worth the money, IMO.

The "pisser" in all of this is that Acura could have installed RL rotors (with remachined center sections, if required) for perhaps another $25 per vehicle. Those are 12.6" front and 12.2" rear. They STILL would have been on the small side, relative to the competition, but at least they'd be "in the running." The TL-S is a faster car than the RL and most certainly deserves those rotors.

Bottom line: Run your Hawk pads with the OEM hardware and live with it. These brakes ARE NOT BAD. They are simply not as good as they could have been for a very small cost difference.

MrHeeltoe

iTrader: (1)

You really are stupid aren't you?

The dispute is between curved and straight vane. No one or two piece. Our claim is that the curved vanes move more air than straight ones, which your citation does support. Likewise, racingbrake utilizes the convergant vane, not the traditional curved vane.

At this point I am only posting to counter the poisonous faulty information you keep posting.

MrHeeltoe

iTrader: (1)

I'd offer you parts for comparison to see for yourself, but you already indicated a hard-hardheadedness beyond reason.

Marcus

harddrivin1le

Hmmmmmm...

These real world test results don't support your statement, "Marcus:"

http://www.zeckhausen.com/testing_brakes.htm#Summary

Open, scroll to the bottom and look at the table. Rotor temps plummet as rotor size (and MASS) increase.

harddrivin1le

The difference in a street car is MOOT, since the splash guards/dust shields (which racing cars don't have) largely impede air flow, meaning that curved vanes yield very little improvement in STREET CAR applications.

Are these test results "poisonous and faulty," Marcus? They directly contradict your statement:

Hmmmmmm...

These real world test results don't support your statement, "Marcus:"

http://www.zeckhausen.com/testing_brakes.htm#Summary

Open, scroll to the bottom and look at the table. Rotor temps plummet as rotor size (and MASS) increase.

MrHeeltoe

iTrader: (1)

Allow me to preface my final post in this thread with an apology. To you for being rude here and there and to the readers for dragging this really simple thread on for so long. It is very difficult to resist the spread of hole-ridden, poorly referenced (by means of taking comments out of context), and single-track information, especially when it is being conveyed so redundantly.


The fact of the matter is curved vanes will move more air than straight ones. This is especially important, to your point, that airflow is particularly limited here. I still don't see why you are arguing.



I stand by this comment. I speak from the reference of the average user here. Not someone who will be tracking their car. Factoring in cost, I see no reason why the RB rotors are not a perfectly suitable upgrade.

If this were a racing forum I could see arguing over this topic, but I already know what works well on the street for this car. The results you have provided are a good example of extreme situations...ones where these users will not likely encounter. I could pick your example apart but I am going to resist. All the readers need to know is that bigger is not better. Buy brakes for your intended use. Extreme brakes for extreme use, upgraded materials for more strenuous conditions than average. Stock stuff for the "I don't care its just a car" crowd. By pigeonholing your advice you are conveying poor information to the general public.

Marcus

harddrivin1le

Rotor temps drop DRAMATICALLY as rotor diameter increases. That drop is more or less proportional to the increase in rotor AREA (which rises to the square of rotor diameter increase).

STREET cars are fitted with splash/dust shields. They impede flow into the rotor, thereby limited the gains that might be seen in a racing car fitted with curved vane rotors. (Race cars generally don't run splash/dust shields).

Bigger isn't ALWAYS better because "too big" won't allow the friction surfaces to maintain their optimal operating temperatures.

12.6" F and 12.2" R (e.g. RL rotors with TL - specific hubs) would hardly be "too big." They'd be perfect - for this car.

You were correct about the TL-S's hub material. Acura shrewdly PAINTED THE HUBS with a paint that is clearly intended to look like aluminum. At least that will help prevent rust...But they are, in fact, iron.

Nevertheless, I would never dump big money into aftermarket rotors of the same size as OEM. I would either leave the rotors stock (which is what I plan on doing) or install a "big brake kit" (which I won't do).

I am still waiting for you to post a THIRD PARTY TEST proving that JUST a change in rotors (same size as OEM, with all other variables the same) is capable of producing significant performance gains in braking (stopping distances and rotor temperature) in a street car (fitted with splash/dust shields).

MrHeeltoe

iTrader: (1)

That won't happen because just changing rotors alone will not reduce stopping distance.

triggle

What has happened to this board. It used to be that an 11 page thread was worth reading. This is nothing more than a pissing contest.

MrHeeltoe

iTrader: (1)

This thread should have been locked days ago. I clearly can't control myself. At least I am not the only one.

Evader

Can't we all just get along? Marcus thank you for the very imformative email. If I knew I could in someway become the "third party tester" I would seriously consider changing out just the rotors and then the pads or whatever would be required to end the damn madness to this thread!

Kennedy

iTrader: (2)

When these stock brakes wear out, I'm doing racingbrakes...
and NOT because I expect shorter stopping distance.

1) They should last forever, Marcus reports most folks getting 3 sets of pads out of the rotor before turning them/replacing the outer ring.

2) They may not result in shorter stopping distance, but should be me more high performance oriented when combined with a more aggresive pad. The curved vanes, and 2 piece design will run cooler no matter how you argue it.

3) They just plain look great with a nice open rim.

For the money Acura charges to do a 4 point brake job (with new rotors), is pretty much the same cost of racingbrakes + good pads and DIY.

My money to waste... and I'm gonna do it.

Evader

^+1 for the RB! At the very least they will be equal to the stock rotors and will def last longer, and least importantly but still a good deciding factor.. They look hot as hell! sometimes you gotta pay to play

My stock rotors are fine for now so I think I'm just going to go with the new pads. I've had my TL-S since march and have 20K miles, so it won't be long before I go through another set of pads. At that time, probably in another 6 months I'll get rear a rear BBK, stainless lines and do the RB rotors/pads!

blacktls07

iTrader: (1)

My car is at 12k and my breaks are already squealing. Going in to get them replaced soon.

XxAfG786xX

that guy always argues, just like he argued about me using teins to lower my car...

V-Sic

damn ppl....fucking change your tampons and move on! Its not that serious! LOL

Evader

I got the 04-06 MT HPS pads for my 07 TL-S 5AT and just didn't install them yet but I can tell they are going to be a perfect fit. This will be my first project for when my car gets out of the body shop!

XxAfG786xX

Brake dust on the brembro's suck...time for ceramic brake pads