harddrivin1le

I said "IN THIS SEGMENT" (i.e. 3,600 pound "performance sedans"). The TL Type S's brakes are SMALL by those standards. In fact, I can't think of a car in this segment that has SMALLER brakes.

Can you?



http://www.bmwusa.com/vehicles/5/528iSedan/techdata.htm
528i:

Brakes
Front - diameter 12.8 inch
Rear - diameter 12.6 inch

Check out the rotor size on the IS350 and the G35 sport...

My statement holds.

What exactly is your point? That stopping power has nothing to do with rotor diameter (and mass)?

Bearcat94

And why do we need the RL brakes again? So you can do multiple, consecutive 120 – 0 stops? Not a good enough reason for me.


Tell me again:

Excluding your fruitless pad break-in(s), how many times have you stopped from more than 80 to 0 repeatedly since you've owned your TL-S?

How many people do you know that have?

Have you tracked your TL-S?

If not, why do insist on performance you won't use? The TL-S is already AMONGST THE BEST of a WIDE VARIETY of modern sports sedans for stopping performance.

AND they have BETTER THAN AVERAGE Swept Area per Ton in that same group.

Bearcat94

I must admit, you are RIGHT ON with this:



Porsche 911 – Pure Sex with those Big Rotors




M3




G35 Bigger Rotor fills the rim nicely




Gotta have that Big Rotor Sentra SE-R Won’t stop, but it sure looks good.




RL A-Spec Concept – HOT! Looks as good as the $160k Porsche! Wish my TL-S had this.




WOW! The TL-S disc looks lost inside even the 17” wheel. A Bigger Rotor would DEFINETLY look better. Good Call!!

harddrivin1le

Why do TL-S buyers "need" 286 HP and a top speed of more than 150 MPH?

Wouldn't the 200 HP V6 from an '01 Accord would be "adequate."

The brakes Acura is putting in the TL-S are the equivalent of that Accord's engine.


Single stop, 80 - 0 or 60 to 0 stopping distances say as much about the TOTAL braking picture as a 0 - 60 acceleration time says about top speed (i.e. NOT MUCH).

Bearcat94

And yet, so few cars stop better. None 60 - 0 actually.

60 – 0 Emergency Stopping is OUT-FUCKING-STANDING compared to a WIDE VARIETY of modern sports sedans, regardless of market segment.

Acura TL-S 60 – 0 = 117 ft

EXCEPT for the BMW 330i, that’s best out of 25 cars with similar straight line performance.

Make & Model…………………........ 60 - 0
BMW 330i………………………......... 116
Acura TL-S…………………......… 117
BMW 335i………………………......... 119
Infinity G35 Sport……………....…. 120
Volkswagon GTI………………....... 120
Mazda MazdaSpeed6………….... 121
Audi A4 2.0T Quattro…………..... 122
BMW 545i………………………......... 121
Mini Cooper S…………………........ 122
Volvo S80 V8 AWD……………...... 123
Lexus GS430………………….......… 126
BMW 325xi……………………........… 123
Subaru Impreza WRX………….... 124
Lexus IS250 AWD……………....… 125
Lexus IS350……………………........ 126
Acura RL…………………….........…… 126
Subaru Legacy 2.5GT spec.B… 126
Infinity G35x……………………........ 127
Toyota Camry SE V6…………...... 127
Lexus IS350……………………........ 128
Mercedes-Benz E350 Sport….. 129
Volvo S40 T5 AWD……………...... 130
Dodge Charger R/T……………..... 132
Mercedes-Benz C350 Sport….. 135
Lexus LS460……………………....... 143


But wait, that’s not all. Against the same group of cars, the TL is WELL INSIDE the top 1/3 in stopping distances from 80 – 0 and at 214 ft SIGNIFICANTLY BETTER THAN AVERAGE.

Make & Model…........……………… 80 - 0
Mazda MazdaSpeed6………...... 207
Infinity G35 Sport……………....... 208
BMW 330i…………………….........… 209
BMW 335i…………………….........… 210
Volkswagon GTI…………......……. 210
Audi A4 2.0T Quattro…………..... 210
Acura TL-S…………...…........... 214
BMW 545i………………….........…… 214
Volvo S80 V8 AWD…………......… 216
Mini Cooper S…………………........ 217
Lexus GS430…………………......... 219
Lexus IS350…………………........… 219
Infinity G35x…………………........… 222
Lexus IS350………………........…… 222
Toyota Camry SE V6…………...... 223
BMW 325xi…………………….......... 224
Lexus IS250 AWD…………......…. 224
Acura RL………………………........... 224
Subaru Legacy 2.5GT spec.B... 225
Mercedes-Benz E350 Sport….. 226
Volvo S40 T5 AWD…………......… 226
Subaru Impreza WRX………...... 227
Dodge Charger R/T…………....... 240
Mercedes-Benz C350 Sport….. 241
Lexus LS460…………………...........251


I’ve read that some of these cars even have Bigger Rotors than the TL. :gasp:


Yet the TL-S stops better. How do you explain that with these itty-bitty little brakes?

Your aversion to data is disturbing for a Mechanical Engineer.

harddrivin1le

I already have explained it - ON MULTIPLE OCCASIONS:

60 to 0 is primariliy a traction limited event, since virtually EVERY car can lock the brakes from that speed.

The results therefore say more about weight transfer, pad material, tire grip, road surface and ABS algorithms than they say about the actual braking system.

The brakes don't have a chance to get HOT with a test like that.

Do you use 0 - 60 acceleration times to attempt to compare top speeds?

Furthermore, those results aren't comparable unless they were obtained by the same driver on the same road surface with the same ambient temperature.

Bearcat94

I know. That's why I keep this handy:

Good thing the TL-S is ABOVE AVERAGE in this critical factor to AVAILABLE STOPPING POWER.

Bearcat94

Fuck that. It's a standard formula CRITICAL to your theory, yet missing. The units are standard for the application.

Bearcat94

No, I am stating a Fact. The TL-S brakes are MORE THAN ADEQUATE for their intended purpose. AND BETTER THAN MOST OTHER MODERN SPORTS SEDANS.

The reason I say this is FACT, is that unlike your speculative theories, I have provided supportive experimental evidence.

A Hypothesis without data is still just a Hypothesis. It's about the Scientific Method. You should try it sometime.

harddrivin1le

Is swearing going to change reality?

Brakes don't get HOT during ONE stop from 60 or even 80 MPH and tire traction (rather than friction horsepower) is the deciding factor in modern cars than even hint at "performance."

To repeat: Road and Track's 80 to 0 and 60 to 0 braking distances say very, very little about how those brakes would hold up under severe use.

FAST CARS USE BIG BRAKES. That's because they need the added stopping power (longer brake torque arm) and heat capacity (more weight) that comes with a larger rotor..

Bearcat94

Without Data, Theory is just a fanciful idea. Google "Scientific Method".

harddrivin1le

Your statement is somewhat true if their "intended purpose" involves nothing more severe than 1 or two panic stops from 80 MPH or less AND if the TL-S owner doesn't mind dealing with the added noise and rotor wear that result from Acura's band-aid fix (overly aggressive pads).

HOWEVER, comparing braking distances that were obtained on different days by different drivers on different asphalt at different temperatures has no basic in scientific method.

The results you posted say absolutely NOTHING about how the TL-S's brakes would fair on a road racing circuit in the hands of an experienced driver. (They would quickly overheat and suffer severe fade, since they are too small to adequately dissipate the additional thermal loads.)

Bearcat94

Christ! What a hypocrite.



Hello Pot, meet Kettle:




Talk about speculation. Prove even ONE of those statements with data.

trancemission

harddriven do you own an acura?

harddrivin1le

I haven't called you a single name....

I have explained to you why comparing braking distances of cars that were tested by different drivers on different road on different days under different conditions has no merit in the scientific method, which demands that ALL OTHER VARIABLES be controlled.


Braking performance under severe duty ultimately comes down to the ability of the rotor to dissipate heat. Larger, heavier rotors are better than that than smaller rotors.

The larger rotor CAN heat up as quickly, but only because the car it's bolted to is stopping harder.

Bearcat94

I KNOW. How many times do I have to post this. This refers to stopping in situations not otherwise tested.

It's your statement of fact. Admit it's wrong and I'll stop using it.

harddrivin1le

Yep...

I've got an '07 TL Type S automatic.

I can scan the registration and e-mail it to you if you need to see it.

The brakes on it are roughly comparable to my '99 Camaro's below 80 MPH or so.

The Camaro's brakes (11.8" F/11.8" R rotors on a 3,380 pound car) had SIGNIFICANTLY more stopping power than my TL-S at elevated speeds. And that Camaro wa sgood by 1999 standards, but not so good by today's.

Bearcat94

So, show ANY reasonable reputable data on stopping distance from above 100 MPH - either one-time or repeated stopping.

If you can't, you've got nothing but air.

harddrivin1le

Larger rotors have longer torque arms and more mass.

That means they have the potential for greater frictional horsepower (stopping power) and superior heat dissipation.

That is fact.

That is why real performance cars have LARGER rotors.

And that is why Honda is fitting 12.6" rotors to their 2,800 pound Civic Type R.

Most modern "performance" cars can lock their brakes from 80 MPH (or below) when the brakes are cold. The brakes therefore aren't the weak link at those speeds. The tires, the pads, the asphalt and the ABS algorithms are.

Bearcat94

You don't KNOW that. You ASSUME that. You EXPECT that. But you don't KNOW that. There may be mitigating factors.


You REALLY should check into this. But make sure you don't stop there, 'cause there's more to the story.

harddrivin1le

There is nothing more to the story.

And if you think there is then "explain" your 1st order, simplistic formula to me and I will tell you why you are WRONG.

The ONLY other variable is clamping force. The pistons on these brakes are pretty small (38 and 42 mm) and the line pressure is the same as an Accord's. Clamping pressure isn't the "mystery."

And IF more clamping pressure were involved then one could expect shortened rotor and pad life.

trancemission

uhh.....no, just wondering

harddrivin1le

http://www.aa1car.com/library/brake_rotors.htm

"The amount of heat that is created at the rotors depends on the speed and weight of the vehicle, and how hard the brakes are applied. A normal stop from 60 mph can easily raise the temperature of the front rotors 150 to 250 degrees. Several hard stops in quick succession can send rotor temperatures soaring into the 600, 700 or even 800 degree range!

If rotor temperatures keep going up because the driver is riding the brakes (as when traveling down a steep mountain) or is driving aggressively, the brakes may get so hot they start to fade. Once this occurs, it takes more and more pedal effort to slow the vehicle. Eventually the point may be reached where the brakes can't generate enough friction no matter how hard the driver stands on the pedal.

Large heavy vehicles like fullsize SUVs and trucks obviously create more braking heat than small passenger cars. Consequently, the rotors on trucks are larger than those on cars. The bigger the rotors, the more heat they can handle. That's why race cars and performance cars typically have oversized rotors -- so they can stop quickly without frying the brakes."

harddrivin1le

http://968s.com/brake.htm

"The rotor must have the necessary mass to absorb the heat generated by applications of the brakes, in effect it is a "heat sink". After the initial temperature "spike" from a hard brake application, the rotor must be able to cool or dissipate the heat ready for the next application."

Bearcat94

Potential? Who's talking about potential?



You stated this as a FACT of brake potential. You then lied and said:

AND

When in fact real data shows the TL-S has plenty of Swept Area per Ton. By the logic you provided, this means that the TL-S has BETTER THAN AVERAGE brake potential at all speeds.

Every peice of data shown thus far supports that.

I hate cars

I haven't read this whole thread but some of the things I'm reading I can't believe. I had this same argument with my friend with the IS350 until we took it to a "track" and raced each other around corners. Just two things to remember...

1.Bigger brakes do not make a difference in braking distances from a single hard stop. As long as you have enough power to lock the wheels or trigger the ABS, you're fine.

In normal driving conditions you will never notice you didn't get the optional Brembos even in a panic stop.

2.Bigger brakes do make a difference in multiple hard stops. They maintain the original stopping power after the smaller brakes fade. Up till that point, the big brakes are doing nothing but adding weight.


You can use harder pads as sort of a bandaid for undersized brakes. Two problems with those.... They can be noisy and they wear rotors out faster.

IMO, 1le is right about the TL-S brakes being undersized for a 3700lb performance car driven on a track. When I think of people who check the big brake option or "S" when buying a car I think of people who occasionally do auto-x. Acura should've offered something in the 13" range as an option especially with so much weight on the front. For people like me where the TL is just transportation, the stock brakes are fine.

For about 90% of TL drivers, if you want better stopping, get a better set of tires. Unless you drive hard long enough to fade the brakes, tires are the best investment.

I see both sides to this and I agree with both... Most people will never see the benefits of the big brakes...but...stock brakes are inadequate for track use.

Want to have some fun, try racing a 600hp Regal with 10.5" brakes and drums in back.

Bearcat94

OK. You say so.

I hope though, that you're not using that Mechanical Engineering degree for anything more critical than to design Paper Cups or Dog Dishes.

harddrivin1le

Tell you what:

Install the brakes from a 2004 Accord Sedan V6 (11.1" F and 10.2" rear) onto your TL-S and let me know how it stops - especially from real speed.

The difference between that and your stock TL-S is about the difference you'd see between a stock TL-S and a TL-S that was fitted with Acura RL rotors (which would of course stop better).

The TL-S has, BY FAR, the SMALLEST ROTORS in it's market segment.

Acura's shrewd use of overly aggressive pads largely masks that fact in modest speed, "panic" stops when the brakes are cold.

These brakes would be a JOKE on a road racing circuit because the rotors are too small to dissipate the that that would be generated by a 3,700 pound car undergoing repeated hard stops.

Bearcat94

Why should I? The TL-S brakes are good. I stop from "real" speed everyday. Sometimes 20 mph, sometimes near 90 mph.


How many times in your TL-S have you had to repeatedly stop from 120+ MPH? Why won't you answer this, I've asked about 5 times?

harddrivin1le

Met to say "to dissipate the HEAT" in the last sentence.

I encourage anyone who is reading this thread to check out the size of the rotors being used by the competition.

And remember, one or two COLD "panic" stops from 60 or 80 says very little about total braking performance, since the brakes in most "performance" vehicles are capable of fully locking all 4 tires at those speeds (meaning the brakes aren't the weak link in such tests). The tires, the ABS algorithms, the asphalt and even weight transfer are.

I hate cars

Wow. Take your guys' last two posts and then read the end of my previous post..

Bearcat94

Of the 80,000+ TL/TL-S sold per year a very, very small number of cars that require the "performance" you desire so much, but will probably never use.

Why do you continue to insist it's important?

Even you admit that the brakes serve their intended purpose and the VAST MAJORITY of drivers.


The way people REALLY brake from speed is encompassed by the 60 – 0, 70 – 0 and 80 – 0 test. I’ve posted those results. They speak for themselves.

harddrivin1le

How many times I stop from 120 MPH isn't relevant to the discussion. I frequently drive at "very significant" speeds on the open road and I like to have the reassurance of REAL brakes when I'm doing that. This car is lacking in that respect. It's not "terrible," but it's not what it easily COULD (and SHOULD) be (12.6 F rotors and 12.2" R rotors from the RL). That would only put it on par (barely) with the competition.

How many times do you go 150 MPH in your TL? Probably never, but it's nice to know that it can COMPETE with other cars in its segment in that area - even if it is an extreme.

The fact of the matter is that this car simply doesn't stop as well as my 1999 1LE Z28 (that I paid $21,600 for - brand new).

They are pretty close in stopping power from 80 MPH or so. The Camaro had SIGNIFICANTLY more stopping power at higher speeds. It enough to lock the belt against my chest at 135 MPH and this TL sure as hell can't come CLOSE to that.

I'd probably think the brakes on this TL were great, too - IF I had never owned the 1LE.

But I did. It is therefore the standard by which I judge all other cars.

And while the 1LE's brakes were "very nice" by 1999 standards, they aren't all that great by more modern performance car standards.

BTW: That "old fashioned pushrod V8" also got fuel mileage that was AT LEAST as good as my TL-S's while simultaneously putting another 60 HP or so to the ground (before I modded it).

Bearcat94

Now maybe you're FINALLY getting it. These are the things that matter when you drive the car:

- It's not the top speed, it's getting the 1st half of it.
- It's not the stopping from 120, it's the stopping from 60.

I hope you FINALLY see the light.

harddrivin1le

I FREQUENTLY drive at very significant speeds on the open road.

These brakes don't provide me with the same level of reassurance that my $21,600, 1999 Camaro did at those speeds.

I hope YOU "finally see" THAT light.

And as good as they were by 1999 standards, those Camaro's brakes are only "decent" by today's standards.

Brakes have progressed further in the past 5 years than they'd progressed in the previous 10. Rotor sizes have increased DRAMATICALLY (relative to vehicle weight) during that timeframe. There's a reason for that. Manufacturers scrimp and save to knock a dime's worth of content out of a car. Yet, they are spending more money on larger rotors.

Bearcat94

That's dangerous and irresponsible. There is no justification for it.


You've mentioned 120 MPH often. If that's what you're implying, then, no, I don't see "that" light. MOST DEFINETLY NOT.

That's 50 - 55 MPH over the Max legal speed in most states. Here it's called Wreckless Endagerment and Wreckless Operation. You kill somebody it's called Negligent Homicide.





If you're going to "FREQUENTLY drive at very significant speeds", take it to a track.


And if you're gonna track your car FREQUENTLY, you've got more than brakes to work on.

harddrivin1le

I don't need an OFF TOPIC LECTURE from you.

My TL-S doesn't stop like I'd like it to (and like it SHOULD) from the speeds that I drive on the open road. It reduced my lack of confidence at speed and makes me feel more vulnerable. I don't like that.

The Acura RL's brakes (which, by the way, are the same brakes that Honda installs on it's 2,800 pound, 197 HP Civic R) would have been much better suited to MY needs.

People who don't understand the physics and engineering behind brakes (most people) fall for the "Brembo" name in Acura's sales literature and ASSume they're getting some really serious brakes.

They aren't.

They're getting a set of "decent" brakes with overly expensive front calipers fitted with overly aggressive pads that stop reasonably well - when cold or warm - from a "panic" stop at speeds below 90 MPH.

The RL's 12.6" F/12.2" R rotors would have produced brakes that are more in line with true high performance brakes. Acura chose not to do that, despite the fact that the TL-S is heavier AND faster than the '04 6 speed cars that these brakes were originally designed for and despite the fact that rotor sizes have increased significantly in most other cars since.

I can GUARANTEE you that the '09 TL will have larger brakes (probably the existing RL's brakes) and that Acura will hype that in their marketing campaign.

The V6 Accord sedan went from 11.1" F/10.2" R brakes in '07 to 11.8"F/11.1"R brakes in '08 (same brakes as the base TL)!

Brakes are coming for the new TL...

60 to 0 "panic stop" results in ROAD AND TRACK will probably be about the same (and could be worse, depending on the road conditions, temperature and driver). Braking on a road racing circuit and/or during repeated stops from elevated speeds will improve significantly.

Bearcat94

It's not Off Topic. You brought it up and asked my opinion.



You claim the brakes are insufficient for high speed use and the brag about "FREQUENT" High Speed runs on the PUBLIC roads.

Who in their right mind would call that responsible?

Bearcat94

You or someone else *could* end up like this:





http://www.topix.com/forum/city/orla...U3FTVS5SGL910S


http://boise.injuryboard.com/motor-v...-kills-man.php

Bearcat94

Or this:




http://www.germantownnow.com/story/index.aspx?id=668264