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Can someone please explain the "Big Brake" craze that's going on? I'm seeing cars with 14", even 15" rotors, with 4 or 6 piston calipers to match. Why would you ever need that much brake on a street car? Is there an actual performance reason for having such large brakes? I would think that the tire is the limiting factor on any street car braking system, and if I can lock up the tires on my car by standing on the brake, I've exposed the "weak link", so to speak. I can see road racing cars using larger brakes due to fade resistance and having stickier road racing slicks, but it seems overkill for the street(and expensive overkill at that). I can't see making repeated stops, or slowing down as much and as often on the street as you would when road racing. I guess it falls more under the "bling bling" factor, or needing something to fill up those 20" rims that are popular too?
 

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On huge wheels (above 20 inches) there is a need for it because they are so heavy that it takes a huge rotor slow that amount of spinning mass down. That is why lifted trucks with big tires should also upgrade their brakes. There also is the obvious bling factor which also playes a big part of it.
 

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More bling in my opinion on a street car. If you can lock up the front tires with the brakes you have then bigger just might ease a little pedal effort. On a road course it'd be money well spent.

A somewhat larger diameter tire is not going to make 15" rotors necessary on a street car.
 

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On 2006-03-17 00:45, 289nate wrote:
More bling in my opinion on a street car. If you can lock up the front tires with the brakes you have then bigger just might ease a little pedal effort. On a road course it'd be money well spent.

A somewhat larger diameter tire is not going to make 15" rotors necessary on a street car.
If you are restricting your opinion to newer cars, Mustangs...I am inclined to agree with you. However, if you look at a lot of the older cars, the "Muscle Cars" and Factory Hot rods of the 50's, 60's even up into the 80's (Buick GN/GNX, Fox-body Fords)...many of those cars, especially when compared to what is being sold today… are severely, under equipped when it comes to braking!

Many (including me) used to avoid the freeway in 60's era cars, Galaxies for example, because little pocket rocket cars would pop in and out of lanes, hit their brakes or dive into an exit ramp with no regard to the much, much longer stopping distance required for a 2 ton car. Even worse, trying to haul down a 400+ horsepower tank, using 10x2, 10.5x2.5 or even 11"x3" drum brakes, is enough to make you grip the seat with every orifice at your command...it sometimes has been the cause of a faith-based reflection and renewed belief in divine, religious intervention.

Anti-lock brakes, disc brakes, better suspensions have brought the driving expectations of many performance drivers to a much higher plane, you step out of your everyday car, drive your “Toy” for a while and its apparent that something has to change.

When a stop requiring in excess of 200 ft, from 60 mph, is cut down by 20% - 25%, you realize that it has nothing to do with "Show 'n Shine", it's about whether you will spend time enjoying your car or parking it.

It’s much better to remember avoiding a collision; just cursing the pimple popping delinquent that just had to squeeze his 12 ft tinker toy into the 13 ft safety zone left when you merged into rush hour traffic…than to sit at the side of the road watching the car you spent 2 -3 years getting just right, being carried off down the road swinging on a hook, on the first step to being recycled into a Toyota.

Most of these older cars needed better brakes when they left the factory, once the engines have been breathed on...it should be a requirement. Disc brakes are not just for show. Moreover, 10" discs are not enough in stop and go traffic where you are constantly hauling down a 3500 - 4000+ lb car.

No doubt some people are Lemmings, just following trends...but that doesn't mean replacment brakes aren't a valid, important safety issue...one that is based on plain, good, old fashioned, common sense. If you upgrade the performance potential of your car, shouldn't you also upgrade the brakes?

The way I see it, the common alternative of using a bridge abutment, light pole, Oak tree or the car in front of you for assistance in stopping is both frowned upon and possibly deleterious for your health, comfort and peace of mind.

<font size=-1>[ This Message was edited by: Beoweolf on 3/17/06 9:29pm ]</font>
 

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Wolf, you said it. The average joe driver doesn't realize or isnt inclined to adapt to the old car he has sitting in his garage for weekends after he spent all week driving his daily driver BMW. I for one can adapt, but still can get caught with my pants down at times in my 65 Gal. Driving a police interceptor Crown Vic for an average of 60 hrs a week can put my unchecked expectations on my classic cars braking and handling ability a little high at times. I distinctly remember the turn I made that led me to park the 65 till its disc brakes were on. I had just made a nice little run on a decent stretch of road and was backing off the gas when i saw my turn. As if in my usual car, I attempted to do last minute breaking and turning when I saw my turn coming up kinda fast. I made the turn, but afterwards I felt guilty to say the least. I really had no business pushing the 65 car to 2005 standards regardless of any skill level.
So stangboy, you see, that is what it is all about. The factories are making cars the way they always should have in the first place in my opinion, (disc brakes were used on military aircraft in the EARLY years, it just wasn't marketed for public use) and people are just following through rather than adapting back to the old school when they drive their older cars. Now enter; marketing. Even if a certain size rotor is plenty, American commerce is only going to sell bigger and better till the demand slows to the point where profits start to lower. Myself, I love to get so much more than I need so I know I wont want right away if ever more. The question of want verses $$$ is really the deciding factor though huh? So do you need HUGE brakes? Probably not. Would you like HUGE brakes? Absolutely. Now how much are you willing to spend? I think anything beyond the year that they first started to put disc brakes on cars have adequate brakes for that particular car. Adequate. You can always go a step further for better performance. In other words 11"rotors to maybe 12" rotors. Seems to me anything beyond that is not so much "overkill" as it is "excess". Now c'mon. We are all into excess when it comes to our cars aren't we? Or do you think 600 HP is neccessary for a typical streetcar? LOL
I myself am putting the typical 11" rotor brakes on my 65 Gal because that is the spindle that I was able to get my hands on with the limited availability. I hope its enough. It is gonna have to be!!
 

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If those 11" brakes stop a 73 Torino as good as it does. A Gal should do just as good!
No its not a 04 Cobra, But they work good.
 

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You also gotta look at your loads - If you've added weight (big block (or wifey's put on a few pounds)) or if you tow bigger brakes are better - anything to decrease stopping distance. The bigger the brake, the LESS hard it has to work / the less heat builds up = you can stop in that same distance AGAIN in a few seconds when the next idiot cut's you and your 23' long truck with tandem axle car hauler off right before they stand on their brakes because they realized they left their brain at home!
 

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for what its worth:

I was stumbling around the 'Net this morning...then thought I remembered seeing some numbers concerning Galaxies ... Drum brakes vs. disc brakes after a conversion.

Check out the Statinless steel brakes site. They have a list of articles about conversions to disc brakes.

http://www.stainlesssteelbrakes.com/magazine.articles

This is part of an article about a 63 Country Squire Station Wagon, its a little bit heavier than a Galaxie so you might expect the Galaxie stopping distances to be a little shorter.

We headed over to ................................. and left the Galaxie in the very capable hands of Jim Sleeper. Sleeper has worked for some of the best-known hot rod shops in Southern California and recently opened up his own shop again. After a couple of days of working on it between other jobs, Sleeper made the Galaxie stop much better and feel new again.

Since we knew you'd want to know just how much better the brakes worked, before we did the swap we took the Galaxie out to a straight, flat, secluded road and did some baseline-measured 60-0 stops. Our distances were no surprise: 198 feet and 210 feet. As the brakes got hotter the distances got much longer. Once Sleeper was finished we went back out to our testing location and observed the difference. The discs stopped the big boat in 175-foot and 173-foot consecutive stops. Brake fade was also much less prevalent with the discs.

<font size=-1>[ This Message was edited by: Beoweolf on 3/21/06 2:34am ]</font>
 

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Lets see, how big are the brakes on a 747? How about on a 100 car feight train. Both come to a stop but it takes time and distance. Bigger brakes on most cars are overkill. Fashion statement. On a racer, rice or otherwise, they last longer and get rid of heat quicker which is a brakes worst enemy. Look at the older 24hr LeMans cars. Disc get rid of heat quicker and are lighter, also easier to change. Weight and speed is the deciding factors. Within building requirements. Tires are also a big factor. Different tread and rubber stop faster. Wider also. ABS systems have pretty much taken the driver out of the stopping loop. Mainly because most people don't know how to drive anymore. A vehicle with a "trailer towing package" comes with bigger brakes because you're dealing with more weight. Simple. Bigger rims are also prone to break easier because of the size of them and stress factors. But they look cool, yeah right, and cost lots of money so it's an ego thing more then anything. $.02 worth In WWII most aircraft used disc brakes, they also used turbo chargers, alumunium and NOS. How long did it take for the general public to see those. Germans also used gas fuel injection. P-38 had a carb that would ice up and rolling over wasn't a good thing either.
 

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My input on big brakes.

First, lemme say I'm going with 12.19" front, and 11.75" rear, inside 17" rims. My car, max...will weigh near 2500lbs. There's a few tricks involved, regarding cooling without drilling/slotting, and weight reduction, but that's top secret, and doesn't apply here anyhow =p.

About locking up your tires determining the 'strength' and 'suitibility' of your braking system, that's bunk bro. As has been said before, 4wheel drums can lock up a car. If you switch to a 'bigger' brake, and keep the same rim/tire size, you're not just increasing the heat exchange rate etc, you're using a bigger lever to stop your wheels/tires. Yes, your tires dictate the limit of your brakes in a PANIC STOP situation, however, do you jam your foot down to the floor at every red light? No. More leverage helps you modulate the pedal, thus controlling your vehicle's stops more effectively...not to mention increasing feel and control at speed, say on the freeway. Confidence in your car and its abilities gets a good driver out of a lot of incidents, but only if the vehicle is capable of delivering the goods. That's one reason for 'slightly' bigger discs, that most people don't really touch on...although it's a very very valid one, and one of the more important ones for a daily driver (edited to stress that the above paragraph is mostly regarding street driven cars, race cars use bigger brakes for the same reasons...and many, many more).

As far as 15" discs etc, yeah, they're sort of overkill...but think about this a minute. 15" discs require a really, really large rim to fit inside lol. But most people don't realize, a larger rim, is a REVERSE lever on the braking system. Imagine taller tires on your rear end....harder to accelerate, yes? Requires steeper gears, yes? Well, brakes have the same difficulty stopping larger diameter wheels/tires, as a motor has accelerating it. IN PARTICULAR, when the majority of that diameter is completely inflexible aluminum (taller tires give, some...that helps...). So, to have the same braking effeciency as stock on say...a Toyota Supra lol, running 20" rims...you need a MUCH larger lever. That's a small part of the reason why people fill the wheels with brakes. Well, that and the fact that every one of those ricers is trying to emulate a european supercar...and you NEVER see those without the brakes filling up the rims =).

Anyhow, just another reason, though one that's more often overlooked, to use larger diameter brakes than you really think you need.

Cris

<font size=-1>[ This Message was edited by: Is1BadFord on 3/21/06 9:47am ]</font>
 
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