Mustang vs. 350Z

[omicron]

I sense a trial coming on. Excommunication!

[Nethead]

I sense a trial coming on. Excommunication!

omicron: Patience, My lad, Patience...It's uninformed ranters like ArchBishop that make Us appear to be sages--and the crasser they become, the greater seems Our knowledge and wisdom...[Genuflects.]? Amen.

[LonghornTX]

How do you figure?
The brake on the Non Brembo Version are about as big, though do lack the multi Piston caliper, and all Z's use the same type of tire, though. We are not talking about the mustangs Crappy brakes here.

STD
FR: 225/45R18 91W
RR: 245/45R18 96W

GT
FR: 245/40R18 93W
RR: 265/40R19 94W

Though my understanding is the current 18's are pretty light. Ither way, I'm not saying it would be faster, but it would be crazy to think it would be that much slower..if at all.

For someone so intent on argueing a point, you sure do not know do your research.

1.  All of the Zs do NOT use the same tire.  Those with the upgraded forged wheels use the RE050A while the standard setup uses Pilot Sports or the RE040.  The increased width (F&R) will generate more mechanical grip, while the shorter sidewalls will give better steering response.
2.  Are you really trying to tell me that there is no discernable difference between the Brembo upgrade and the standard package?  Not only are the rotors of larger diameter (both F&R), they are also wider as well (better for heat dissapation).  In addition they use stiffer, 4-piston calipers on the front, replacing the stock 2-piston (IIRC, JYODER can probably correct me here) setup and replace the rear single piston setup (again, this is from memory and quick research does not yield an answer) with a 2-piston setup.  I would say that is a pretty significant upgrade myself, even if the rear uses a 2-piston setup.

The upgraded tires (both in quality and sizing), lighter forged wheels, and braking package yields a much more track ready package in the GT model than in lesser models.  If you do not think those will yield a discernable difference on an open track, well, I would say you do not really know what you are talking about. 

[MX793]

The Brembo brakes actually don't really perform any better than the non-Brembos.  They operate at lower temperatures, so in prolonged hard use they may not fade quite as quickly, but stopping distances are only marginally better.

Here's a brake test using a Brembo-equipped 350Z Track and a non-Brembo 350Z "Performance".  Both cars equipped with the same tires.
http://www.zeckhausen.com/testing_brakes.htm

350Z Track average braking distance
60-0:  117.3 ft
80-0:  208.7 ft
100-0:  328.3 ft


350Z Performance avg braking distance
60-0:  118.0 ft
80-0:  210.5 ft
100-0:  333.6 ft

[LonghornTX]

The Brembo brakes actually don't really perform any better than the non-Brembos.? They operate at lower temperatures, so in prolonged hard use they may not fade quite as quickly, but stopping distances are only marginally better.

Here's a brake test using a Brembo-equipped 350Z Track and a non-Brembo 350Z "Performance".? Both cars equipped with the same tires.
http://www.zeckhausen.com/testing_brakes.htm

350Z Track average braking distance
60-0:? 117.3 ft
80-0:? 208.7 ft
100-0:? 328.3 ft


350Z Performance avg braking distance
60-0:? 118.0 ft
80-0:? 210.5 ft
100-0:? 333.6 ft

That is interesting, but really that website only confirms what I was thinking.  For the first lap or two (or in this case couple stops), the two braking systems would perform almost identically because of the similar rotor sizes but after that the Brembo system would hold the advantage becaue of the better cooling characteristics of the system.

Some quotes about the non-brembo setup:
"After six stops from 80mph, and then four stops from 100 mph, the front rotors reached 804 ?F and the stopping distances began to increase as fade set in."

And now, in comparison to the brembo setup:
"The Brembo brakes didn't seem to make a significant difference on stopping performance until the cars started doing repeated 100mph stops, at which point the increased thermal capacity of the bigger rotors kept brake fade at bay, while the Performance model with smaller brakes began to experience fade."

Essentially, the Brembo setup is a more worthy "trackable" option because over the course of any kind of open course session they would resist fade much better than the non-brembo option (look at those operating temps  ).  One thing I did notice is that the brembo car was equipped with the same size tires as the non-brembo car, thus making this not a true comparison of the two cars respective performances as per factory specs.

[ArchBishop]

I Just read through the rules, and the Z is allowed:
Cams
Ecu
Clutch/Flywheel
Front Caliper Upgrade
Nismo Areo kit
Header/Exhaust
Camber Adjustment
SMALLER Wheels (245/40/17 X 275/40/17)

The Mustang is allowed:
Bigger wheels (275/35/18 )
New 5.0 motor with at least 420hp
new Transmission
Driveshaft
Brake upgrade
Front and Rear Suspension Mod
Different ABS system
Steeda "Areo kit"
Chassis Stiffening...(?)
And Fuel cell Behind the rear Axel (bador good?)


Gee....I wonder who is getting the short end of the stick.

Again. Every Z is running the Pre-Rev up VQ motor. The Rev up motor has a Higher redline, better internals, and More power. A 287 350Z will dyno in the 235-245hp range(and that is considered good). A Rev up will dyno in the 250-260hp range. Stock.
A Stock 287 Vq with cams
Again, even with every mod listed, your looking around 260-270hp to the wheels or about 320bhp. and 2900lbs. Further more, the Z isn't allowed to run With 18 inch wheels, and is restricted to the 17's. And the Z doesn't have the option of using a different ABS program.

For comparison, the Cammer motor is good for 420hp, and lets say air restrictors drop output to around 390hp, it gets the same 3.55 gearset the Z gets (though, I don't think that is available on a production mustang) meaning it can multiply its output just as effectively as a Z does.

All cars are required to run Koni Struts, and get to modify camber for lowering 3.5inches, but the mustang Actually gets redesigned front and rear supsension components, while the Z runs on Fairly unmodified suspension geometry.

And even with that all said is the mustang, at an estimated 390 Crank Hp, and 3200lbs, STILL will have a better lb/hp over the Z. And I'm being optimistic about the Z's power figures.

And this agian, moves further from the subject that the stock Mustang is a Turd, and isn't even a match for the Z.

[ArchBishop]

For someone so intent on argueing a point, you sure do not know do your research.
1.? All of the Zs do NOT use the same tire.? Those with the upgraded forged wheels use the RE050A while the standard setup uses Pilot Sports or the RE040.? The increased width (F&R) will generate more mechanical grip, while the shorter sidewalls will give better steering response.
2.? Are you really trying to tell me that there is no discernable difference between the Brembo upgrade and the standard package?? Not only are the rotors of larger diameter (both F&R), they are also wider as well (better for heat dissapation).? In addition they use stiffer, 4-piston calipers on the front, replacing the stock 2-piston (IIRC, JYODER can probably correct me here) setup and replace the rear single piston setup (again, this is from memory and quick research does not yield an answer) with a 2-piston setup.? I would say that is a pretty significant upgrade myself, even if the rear uses a 2-piston setup.

The upgraded tires (both in quality and sizing), lighter forged wheels, and braking package yields a much more track ready package in the GT model than in lesser models.? If you do not think those will yield a discernable difference on an open track, well, I would say you do not really know what you are talking about.?

All 2007 350Z's get the RE50 tires.
http://nissannews.com

And as MX pointed out, the stopping distances between the Brembos, and the Regular brakes are similar, with the slight difference maybe due to the bigger front tires (added grip).

Nice try. And I'm Trying to find the Wieght of all the Z wheels with no Success.

[LonghornTX]

All 2007 350Z's get the RE50 tires.
http://nissannews.com

And as MX pointed out, the stopping distances between the Brembos, and the Regular brakes are similar, with the slight difference maybe due to the bigger front tires (added grip).

Nice try. And I'm Trying to find the Wieght of all the Z wheels with no Success.

You are right about the tires.? I took my info from tirerack.com, so I guess they must have their info wrong as it does indeed list the RE050As for all Zs on the nissan website.

Yes, the stopping distances in that test were similar for the two packages, but as the brakes started to heat up the Brembos resisted fading while the stock brakes faded.? Thus, in any kind of track environment (and not single passes where the car is stopped completely to measure the temp), short of autocross, the Z equipped with the Brembos will indeed perform better.? Anything over 3 laps on any track of decent length and the Brembo car is going to really show a performance increase.? Infact, in the opinion of the testers, "I don't think the Performance model will stand up to any serious track use unless the brakes are upgraded."? The same was not said of the Brembos.

Also, if you had read my post (or the link that MX posted), you would see that the two cars in the this test were equipped with the same size, brand, and style of tire (I believe they were RE040s), thus negating the positive benefits on braking distances that the GT would normally enjoy.? From the website,
"All the tests (except the 4-wheel brake upgrade) were to be conducted using the same tire make and model in the same size and on the same size wheels."

So, not only does the Brembo equipped car stop slightly shorter (without the above mentioned tire benefit), but it also has much better heat management properties.? This, in addition to the wider tires it employs, easily makes the GT the most track oriented model of the Z range.  It also has a lowed Cd and better downforce (from what I hear), but we will leave that out of this discussion.

[JYODER240]

All 2007 350Z's get the RE50 tires.
http://nissannews.com

And as MX pointed out, the stopping distances between the Brembos, and the Regular brakes are similar, with the slight difference maybe due to the bigger front tires (added grip).

Nice try. And I'm Trying to find the Wieght of all the Z wheels with no Success.

Here is a link for 03-05 non-35th wheel weight:

http://www.350zmotoring.com/modules.php?s=&mop=modload&file=index&name=Wheels

I don't know what the 35th, 06 and 07 wheels weigh.

[Nethead]

Again. Every Z is running the Pre-Rev up VQ motor. The Rev up motor has a Higher redline, better internals, and More power. A 287 350Z will dyno in the 235-245hp range(and that is considered good). A Rev up will dyno in the 250-260hp range. Stock.
A Stock 287 Vq with cams
Again, even with every mod listed, your looking around 260-270hp to the wheels or about 320bhp. and 2900lbs. Further more, the Z isn't allowed to run With 18 inch wheels, and is restricted to the 17's. And the Z doesn't have the option of using a different ABS program.

For comparison, the Cammer motor is good for 420hp, and lets say air restrictors drop output to around 390hp, it gets the same 3.55 gearset the Z gets (though, I don't think that is available on a production mustang) meaning it can multiply its output just as effectively as a Z does.

All cars are required to run Koni Struts, and get to modify camber for lowering 3.5inches, but the mustang Actually gets redesigned front and rear supsension components, while the Z runs on Fairly unmodified suspension geometry.

And even with that all said is the mustang, at an estimated 390 Crank Hp, and 3200lbs, STILL will have a better lb/hp over the Z. And I'm being optimistic about the Z's power figures.

And this agian, moves further from the subject that the stock Mustang is a Turd, and isn't even a match for the Z.

ArchBishop:  Actually, ArchDude, there is some worthwhile stuff in this posting of yours.  I knew you could do it even if others had given up all hope!

About wheel sizes:  There is a Grand American Cup certification procedure similar to homologation in Europe.  Whomever it was that got 350Zs certified--some racing team (or teams) since Nissan wasn't interested--chose to use the 17" wheels for certification, probably because they performed better than had been their experience with 18" wheels.  You may correct the Nethead here if you find evidence which shows that whomever certified the 350Z asked to have 18" wheels approved but the officials refused.  A 17" wheel and tire saves unsprung weight, and also will require less of the engine's power to spin at the same RPM as an 18" wheel and tire.  It's a trade off since one turn of an 18" wheel and tire produces more forward distance than does one turn of a 17" wheel and tire.  If it's an issue for you, investigate it! 
Ford and Multimatic went with 18" wheels and tires from day one because the T50 had the power to accelerate those 18-inchers plenty fast and to wind them on up to redline in fifth gear. 

ABS:  The Mustang has two choices--and I believe it's because some performance wheels have an integral toner ring and some performance wheels do not.  If you want to use ABS at all (not mandatory), you select the ABS that works with the wheels you'll be using--Mustang FR500Cs come with Fikses, but those moving up from earlier model Mustangs probably want to use as much of the hardware they can from their previous Mustangs, and there were teams that did just that.  Some teams are lucky enough to have wheel manufacturer sponsorships so you know whose wheels they will insist upon using.  If that's the case, Ford can probably accommodate your wheels with one or the other of the ABS components.  This saves you having to invest in more sets of wheels--Fikses were $4,000 for a set of four back in '05, and you'll need two sets at the very minimum so you'll have a tire already on a wheel if you have one starting to lose air during the race.  It's also helpful to have a set dedicated to rain tires, too.  This is just sensible thinking about the little guy in racing, y' know?  Save 'em money any way you legally can.

3.55:1 rear end ratios:  This is a punitive ratio, but barely...Back in '05 they required that the Mustangs switch from something like 3.31:1 to cut their awesome top speed--so the officials mandated something like 4.10:1.  The top speed did indeed go down, but then they could accelerate like afterburners off the corners and continued winning because they were still the vehicles with the highest top speed on long straights (the advantages of DOHCs coming through here).  The officials then mandated something in the mid 3s, although the Nethead here cannot tell you if it was 3.55:1 at first like it is today.  It's meant to be very punitive, but with the power of the T50 there's still plenty of top end and still plenty of acceleration.  If I get motivated, I may see if I can find what rear end ratio the FR500Cs were equipped with originally--which may be what was found to be the best ratio for balanced performance in the car as certified.

Stock Mustangs:   The cheapest and best 300 HP available in America, period.  On regular unleaded.  And they're great!  They also are practical enough to live with for many years--that fold-down back seat yields a lot of cargo capacity in a small two-door coupe.  Mustang has more repeat buyers than any car model sold in America--domestic or foreign.  One-touch windows, remote side mirrors, 500 amp and 1000 amp sound systems, and the largest aftermarket in the history of the Earth--not to mention at least twenty-four companies turning out tuner versions with horsepower ranging from a little above stock to a twin-turbo 900 HP--even Germany has a 180 MPH tuner version with 520 HP!  And every Ford engine fits without sledgehammering the wheelwells or Sawzalling the firewall--even the Aston Martin Vanquish V12 snuggles nicely in the engine bay with plenty of wheelwell clearance for headers (a blessing of a sixty-degree engine).  And splendid resale when you've had your fun and want to trade for another.  Where else can you get 500 HP and 480 feet pounds of torque for $40,930?

[Minpin]

Just accept that facts nethead. 350Z>mustang. Forever. 

[565]

Here is a link for 03-05 non-35th wheel weight:

http://www.350zmotoring.com/modules.php?s=&mop=modload&file=index&name=Wheels

I don't know what the 35th, 06 and 07 wheels weigh.

Found them

http://240sx-tech.com/zwiki/Wheel_Specifications

Wheel Version? Front Weight? Rear Weight?
Standard 17"? 23.26? 24.14? lbs
Touring 18" v.1? 26.56? 26.56? lbs
Track 18" v.1? 18.19? 18.62? lbs
Touring 18" v.2? 24.8? 25.8? lbs
Track 18/19" v.2? 21.25? 29.50? lbs

So the new Track rims are 18/19, and the rears are the heaviest 350Z rims of all (due to size), while the front ones are slightly lighter than standard.? Still the first generation track rims are the lightest of all, by more than 10 pounds in the case of the rears.

In terms of total weight there is actually disadvantage to the 18/19 track rims compared to base or touring rim, so there goes that theory.



And just to troll.
02' Z06 spun cast rims

http://www.superhonda.com/tech/wheel_weights.html

Chevrolet Corvette Z06 02 Cast/Spun 17x9.5 19.2 lbs (front)
Chevrolet Corvette Z06 02 Cast/Spun 18x10.5 21.0 lbs (rear)

[LonghornTX]

Found them

http://240sx-tech.com/zwiki/Wheel_Specifications

Wheel Version  Front Weight  Rear Weight 
Standard 17"  23.26  24.14  lbs
Touring 18" v.1  26.56  26.56  lbs
Track 18" v.1  18.19  18.62  lbs
Touring 18" v.2  24.8  25.8  lbs
Track 18/19" v.2  21.25  29.50  lbs

So the new Track rims are 18/19, and the rears are the heaviest 350Z rims of all (due to size), while the front ones are slightly lighter than standard.  Still the first generation track rims are the lightest of all, by more than 10 pounds in the case of the rears.

In terms of total weight there is actually disadvantage to the 18/19 track rims compared to base or touring rim, so there goes that theory.



And just to troll.
02' Z06 spun cast rims

http://www.superhonda.com/tech/wheel_weights.html

Chevrolet Corvette Z06 02 Cast/Spun 17x9.5 19.2 lbs (front)
Chevrolet Corvette Z06 02 Cast/Spun 18x10.5 21.0 lbs (rear)

Nevermind then about the rims.  Those sure are some heavy forged rims; 29.5 lbs for a 19 inch rim is unacceptable in my book  .

Those Z06 wheels, on the otherhand, are pretty dang light!

[ChrisV]

That is interesting, but really that website only confirms what I was thinking.  For the first lap or two (or in this case couple stops), the two braking systems would perform almost identically because of the similar rotor sizes but after that the Brembo system would hold the advantage becaue of the better cooling characteristics of the system.

Some quotes about the non-brembo setup:
"After six stops from 80mph, and then four stops from 100 mph, the front rotors reached 804 ?F and the stopping distances began to increase as fade set in."

And now, in comparison to the brembo setup:
"The Brembo brakes didn't seem to make a significant difference on stopping performance until the cars started doing repeated 100mph stops, at which point the increased thermal capacity of the bigger rotors kept brake fade at bay, while the Performance model with smaller brakes began to experience fade."

Essentially, the Brembo setup is a more worthy "trackable" option because over the course of any kind of open course session they would resist fade much better than the non-brembo option (look at those operating temps  ).  One thing I did notice is that the brembo car was equipped with the same size tires as the non-brembo car, thus making this not a true comparison of the two cars respective performances as per factory specs.

Remember, the brakes do not stop the car, the tires do, given no brake fade. So the stopping distances being equal would come down to the tires being the same levels of grip. As you surmised, however, the advantage is in lack of fade for heavy duty use.

[565]

Remember, the brakes do not stop the car, the tires do, given no brake fade. So the stopping distances being equal would come down to the tires being the same levels of grip. As you surmised, however, the advantage is in lack of fade for heavy duty use.

Sometimes braking distances are just unexplainable.

From http://www.caranddriver.com/shortroadtests/7082/infiniti-g35-6mt.html

"Despite wearing the skinniest rubber, the G35 still shorted them all, posting a distance of 153 feet from 70 to 0 mph. That's less than the pavement needed by the Z (164), G35 coupe (157), 330i (158), and even the Lamborghini Murci?lago (155) and the Saleen S7 (156). Perhaps Nissan had some leftover brakes from the R390 GT1 supercar. "Hey, Taka, what should we do with these fancy brakes"

But the fact is the G35 came with smaller rubber, less sticky rubber, smaller brakes, but still outstopped some impressive competition.

[Nethead]

565:  How 'bout a better ABS system?  The Nethead here does not know if the G35 had a better ABS system, but that factor should be considered...

[565]

565:? How 'bout a better ABS system?? The Nethead here does not know if the G35 had a better ABS system, but that factor should be considered...

Well the G35 probably has the same system as the Z and G35 coupe, but it still outstopped those despite smaller rubber and brakes.  That particular G35 also stopped better than the new G35 sedan. Sometimes cars just stop better, and it's hard to explain.

[JYODER240]

Well the G35 probably has the same system as the Z and G35 coupe, but it still outstopped those despite smaller rubber and brakes.? That particular G35 also stopped better than the new G35 sedan. Sometimes cars just stop better, and it's hard to explain.

Those tests were probably all done on seperate days on different tracks. The level of grip on the pavement will affect braking distances.

[FordSVT]

Remember, the brakes do not stop the car, the tires do, given no brake fade. So the stopping distances being equal would come down to the tires being the same levels of grip.

That's not quite accurate. A car's stopping power is limited to the friction generated between the road surface and the tires, but the brakes still stop the car. Bigger brakes are better able to maximize the stopping power of a set of tires. Given an equally super-sticky set of tires, but one car having 4-piston, 17" cross drilled rotors and ceramic composite pads, and the other car has the brakes from a 1997 Nissan Sentra, it's pretty obvious which car is going to be better able to stop from 100 mph.

But yes, brake fade and control are extremely important when comparing brakes. Most street equipment quickly becomes useless during track use.
-FordSVT-

[ChrisV]

That's not quite accurate. A car's stopping power is limited to the friction generated between the road surface and the tires, but the brakes still stop the car. Bigger brakes are better able to maximize the stopping power of a set of tires. Given an equally super-sticky set of tires, but one car having 4-piston, 17" cross drilled rotors and ceramic composite pads, and the other car has the brakes from a 1997 Nissan Sentra, it's pretty obvious which car is going to be better able to stop from 100 mph.

If the brakes can lock the tires up, they are adequate to stop the car in teh same distance as teh fancy brakes.

http://www.teamscr.com/grmbrakes.htm

Read it. The brakes do not stop the car.

"In plain English, your brakes convert ?the energy of motion? into ?heat? An engineer would say the brakes are responsible for turning the kinetic energy of your speeding car into thermal energy. But in either case, your brakes are not stopping your car."

http://www.stoptech.com/tech_info/wp_rearbrake_upgrades.shtml

" Contrary to popular belief, the real reason sports- and racing cars use big brakes is to deal with heat. Period. There has been a bunch of stuff published which will disclaim this, but when you look at the braking system from a design standpoint, making them 'bigger' doesn't fundamentally do anything for stopping distance. It's all about the heat."

http://www.stoptech.com/tech_info/wp_brakesystems_upgradeselections.shtml

"1) The brakes don't stop the vehicle - the tires do. The brakes slow the rotation of the wheels and tires. This means that braking distance measured on a single stop from a highway legal speed or higher is almost totally dependent upon the stopping ability of the tires in use - which, in the case of aftermarket advertising, may or may not be the ones originally fitted to the car by the OE manufacturer.

2) The brakes function by converting the kinetic energy of the car into thermal energy during deceleration - producing heat, lots of heat - which must then be transferred into the surroundings and into the air stream."

But yes, brake fade and control are extremely important when comparing brakes. Most street equipment quickly becomes useless during track use.
-FordSVT-

That is true. Bigger brakes don't let the car stop any shorter, they only let it stop short consistently.

"For maximum brake potential, vehicles benefit from proper corner weight balance, a lower CG, a longer wheelbase, more rear weight bias and increased aerodynamic down force at the rear."

The Mustang has demonstrably worse tires, stock, it has more nose weight (though not as much as some would think) and a higher CG. So it's braking performance vs a TRACK version of the Z is lessened. But the TRACK version vs GT is not what we are discussing here in the original post. The track version of the Z has not, to my knowledge, been run against the Shelby, that also has better upgrades in suspension and braking. (and tires, IIRC)



Oh, and crossdrilling ONLY gives more chance for cracks, it does NOTHING else. It does NOT aid in cooling the brakes. Pads do not outgas anymore, so even THAT reason is not there.

http://www.stoptech.com/tech_info/wp_brakesystems_upgradeselections.shtml

"For many years most racing rotors were drilled. There were two reasons - the holes gave the "fireband" boundary layer of gasses and particulate matter someplace to go and the edges of the holes gave the pad a better "bite".

Unfortunately the drilled holes also reduced the thermal capacity of the discs and served as very effective "stress raisers" significantly decreasing disc life. Improvements in friction materials have pretty much made the drilled rotor a thing of the past in racing."

http://www.teamscr.com/rotors.htm

"Crossdrilling your rotors might look neat, but what is it really doing for you? Well, unless your car is using brake pads from the 40?s and 50?s, not a whole lot. Rotors were first ?drilled? because early brake pad materials gave off gasses when heated to racing temperatures ? a process known as ?gassing out?. These gasses then formed a thin layer between the brake pad face and the rotor, acting as a lubricant and effectively lowering the coefficient of friction. The holes were implemented to give the gasses ?somewhere to go?. It was an effective solution, but today?s friction materials do not exhibit the same gassing out phenomenon as the early pads.

For this reason, the holes have carried over more as a design feature than a performance feature. Contrary to popular belief they don?t lower temperatures (in fact, by removing weight from the rotor, the temperatures can actually increase a little), they create stress risers allowing the rotor to crack sooner, and make a mess of brake pads ? sort of like a cheese grater rubbing against them at every stop. (Want more evidence? Look at NASCAR or F1. You would think that if drilling holes in the rotor was the hot ticket, these teams would be doing it.)"

[FordSVT]

If the brakes can lock the tires up, they are adequate to stop the car in teh same distance as teh fancy brakes.

http://www.teamscr.com/grmbrakes.htm

Read it. The brakes do not stop the car.

"In plain English, your brakes convert ?the energy of motion? into ?heat? An engineer would say the brakes are responsible for turning the kinetic energy of your speeding car into thermal energy. But in either case, your brakes are not stopping your car."

http://www.stoptech.com/tech_info/wp_rearbrake_upgrades.shtml

" Contrary to popular belief, the real reason sports- and racing cars use big brakes is to deal with heat. Period. There has been a bunch of stuff published which will disclaim this, but when you look at the braking system from a design standpoint, making them 'bigger' doesn't fundamentally do anything for stopping distance. It's all about the heat."

Exactly. Perhaps I didn't explain myself as well as I could have. Small brakes can't handle heat at high speeds at all, and they often begin to fail almost immediately when you try to use them. A larger surface area allows pressure to be distributed more evenly over the braking surface which allows for more control and heat dissipation. There were a couple of times in my Sentra when I was driving very fast (100 mph+) and tried to apply the brakes quickly, I could feel them fade immediately. A minute later when I came off the highway and pulled into a gas station, they could barely stop the car. The point about being able to lock up the brakes is correct, but larger brakes also allow you to control whether or not you lock up your brakes. Also, locking up the brakes isn't the quickest way to stop your car unless the pavement is smooth and dry.

I guess your point is taken that using the same materials and applying the same pressure to the rotor in a one-time stopping situation, merely changing the size of the brakes won't matter if the stopping power is the same, the tires are the mitigating factor.

But in the real world, when all things are concidered, bigger brakes usually equals better stopping power and control and fade resistance, all good things.
-FordSVT-