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Old 07-22-2012, 10:54 PM   #11
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The warranty would be void since that rear end is no longer covered.

You have to understand, warranties are NOT made to cover your ass. They are made to cover Fords. The sooner they can void it, the less they might have to spend for any repairs.

Personally, it's not a performance car. Discs are nice, but not a huge need on such a car.

Fwiw, I had discs on mine and it still wasn't enough force to stop me from crashing. I'd have required carbon ceramic for that kind of power.
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Old 07-23-2012, 08:35 AM   #12
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Quote:
Originally Posted by MyThIc3LiTe View Post
Say goodbye to your warranty for starters.

It's a fwd car...rear discs are a pointless luxury since the front really is doing all the work.
Oh here we go again... Another physics expert... Golly, why even put rear brakes on the car at all, the front brakes do all the work!!

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Originally Posted by MyThIc3LiTe View Post
The warranty would be void since that rear end is no longer covered.

You have to understand, warranties are NOT made to cover your ass. They are made to cover Fords. The sooner they can void it, the less they might have to spend for any repairs.

Personally, it's not a performance car. Discs are nice, but not a huge need on such a car.

Fwiw, I had discs on mine and it still wasn't enough force to stop me from crashing. I'd have required carbon ceramic for that kind of power.
No, warranties are are made to sell more cars.

"The warranty would be void since that rear end is no longer covered." -- WTF are you even talking about here??

Whether it's a "performance car" or not is irrelevant. It takes the same braking force to stop a 3,500 lb car with a 160 HP I4 that it takes to stop a 3,500 lb car with a 650 HP V10. (The bias would likely need to be different on the V10 vehicle with what is likely a higher % of static weight over the front axle.)

I myself would like to have rear discs (though not enough to go through the hassle of a conversion). Not for braking performance, but because they're a hell of a lot easier to work on.

Last edited by Pretherius; 07-23-2012 at 12:06 PM.
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Old 07-23-2012, 08:49 AM   #13
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The point about nose dive doesn't really make any sense because braking with the rear wheels exclusively still causes this effect...
Actually I believe the rear would squat. You would have to have braking force on the front to cause it to dive. You can't endo a bike by using the rear brake only.
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Old 07-23-2012, 11:49 AM   #14
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Actually I believe the rear would squat. You would have to have braking force on the front to cause it to dive.
Only if you're driving in reverse when you hit the brakes. :)

It's not the brakes that cause the front end to dive, it's the deceleration of the vehicle. Decelerating the car shifts its weight forward so there is a lot more weight over the front suspension in a hard stop.

To be clear regarding earlier posts, I would NOT advise swapping to rear discs if braking performance is your goal. The car is tuned from the factory for proper braking bias, and I rather doubt that simply swapping the drums and shoes for discs and pads is going to improve your stopping distances; at best they'll likely be the same and at worst your braking distance could get significantly worse.

Remember, it's the interaction between your tires and the pavement that's the limiting factor here. If your brakes are powerful enough to lock all your wheels (which is true of any new factory car), making your brakes more powerful isn't going to help unless you've installed such wide, sticky tires that your stock brakes can't make use of the increased contact patch.

For example, many "tuners" will go and put massive front rotors and calipers in, thinking their car will stop on a dime, when all they've done is cause increase front bias to the point that their front wheels lock up way too early, while the rears still have unrealized braking potential that can't be used without locking up the fronts.

Even more common, people will install more aggressive aftermarket racing pads on the front and, for the reason I just mentioned, see their stopping distances INCREASE.

Some of this is admittedly moot as we're dealing with ABS, but I wouldn't be in a hurry to go spend a bunch of money and lots of my time to make a "performance" upgrade that doesn't help and possibly harms.
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Old 07-23-2012, 05:01 PM   #15
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I'm upgrading mine not so much to improve stopping distance just to make it shorter, but keep at least the current stopping distance more consistantly when doing repeated heavy braking while autocrossing. My goal here is to improve brake cooling so A. I don't get fade as quickly.. and to keep the brake fluid below its boiling point, when driving agressively.

My warranty is void as soon as they find out the car is being driven in off road competition anyway.

And the final reason.. discs are SO much easier to work on.. I absolutely HATE trying to remove and reinstall those damn Jesus springs... (JESUS! where the hell did that just go!?!)
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Old 07-23-2012, 06:28 PM   #16
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And the final reason.. discs are SO much easier to work on.. I absolutely HATE trying to remove and reinstall those damn Jesus springs... (JESUS! where the hell did that just go!?!)
Damn those springs straight to Hell!!!
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Old 07-23-2012, 06:51 PM   #17
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Originally Posted by Pretherius View Post
Only if you're driving in reverse when you hit the brakes. :)

It's not the brakes that cause the front end to dive, it's the deceleration of the vehicle. Decelerating the car shifts its weight forward so there is a lot more weight over the front suspension in a hard stop.
+1. Weight is being transferred back to front no matter what.

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To be clear regarding earlier posts, I would NOT advise swapping to rear discs if braking performance is your goal. The car is tuned from the factory for proper braking bias, and I rather doubt that simply swapping the drums and shoes for discs and pads is going to improve your stopping distances; at best they'll likely be the same and at worst your braking distance could get significantly worse.
How is brake bias handled? Is there an electronic module or is it something mechanical? Trying to figure out what would be different between the braking systems between the S and SE besides the rear drums or discs, respectively (or in this case between the SE and SE Sport, I suppose).
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Old 07-23-2012, 09:07 PM   #18
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How is brake bias handled? Is there an electronic module or is it something mechanical? Trying to figure out what would be different between the braking systems between the S and SE besides the rear drums or discs, respectively (or in this case between the SE and SE Sport, I suppose).
From everything I've seen.. Front brakes are identical for all trim levels. (not including the ST which is its own unique animal...)

As far as rear brakes..

For S's and SE's with drums... no common parts are shared on the rear axle with their disc brake equipped siblings.....(except as noted)

Hubs and Bearings are specific to each type
Backing plates are different.
Brake hoses are different..
Parking Brake Cables are different

Now... Wheel speed sensors for the ABS appear to be the same part between the 2 systems and mount behind the hub..
Master cylinders are the same between all trims with the exception of a second cylinder for the clutch on manual transmission cars.. sharing a central brake fluid reservoir...

Brake Proportioning (Bias) is handled electronically by the ABS/ESC system..
so there is no traditional mechanical style proportioning valve

(Paraphrased loosely from the Service Manual...)

upon initial brake application full line pressure is allowed to reach the rear brakes until the rear wheel speed sensors detect slippage.. at which time the system locks the valves to the rear brakes closed holding line pressure at what it was right at the point the wheels start to slip, while letting front brake pressure continue to build. If the rear wheel speed sensors continue to detect increasing slippage, the system opens the rear brake dump valves lowering rear brake line pressure until the rear wheels recover and the process repeats.. The system constantly adjusts front/rear line pressures based on wheel slippage detected by the ABS sensors and ABS/ESC/ETC system module.
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Old 07-23-2012, 09:37 PM   #19
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Quote:
Originally Posted by MyThIc3LiTe View Post
The warranty would be void since that rear end is no longer covered.

You have to understand, warranties are NOT made to cover your ass. They are made to cover Fords. The sooner they can void it, the less they might have to spend for any repairs.

Personally, it's not a performance car. Discs are nice, but not a huge need on such a car.

Fwiw, I had discs on mine and it still wasn't enough force to stop me from crashing. I'd have required carbon ceramic for that kind of power.
Oh my god...I wish people would get a clue about warranties before throwing the the completely incorrect phrase "void your warranty" around.

Guys... nothing gets "voided". The only time the term void will get applied to a factory warranty, is if someone has modified the engine or trans somehow and causes damaged that was reported to Ford by the dealer. Then Ford may, and sometimes does, void your POWERTRAIN warranty. Nothing else on the car gets "voided".

If you go to a dealer with non-stock parts and either they fail, or they cause something else to fail, they are not going to void anything. They will just deny the warranty claim and you will wind up paying for the repairs out of your pocket. There's really not much more to it that that.

As for installing OE parts that come on different models of the same car....no, that won't be covered. It's still not what came on the car. Every part number of every part installed on a car from the factory is recorded by Ford. If the dealer tries to put a claim through with a part number that doesn't match the build, Ford will reject the claim.
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Old 07-24-2012, 08:29 AM   #20
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There is the possibility that the rear drum setup has the same physical bias as the rear disc setup. I don't know enough about Ford's design to say. With the electronic biasing, it may not matter a whole lot either way. Either way, you're not likely to improve things with a rear brake conversion alone.

Before we had ABS/ESC on every new vehicle, some cars with traditional proportioning valves did come with standard rear drum but optional 4-wheel disc. In those cases, either the disc setup and drum setup had the same bias, or else the proportioning would have had to be different depending on the rear brake setup. I suspect it would generally be cheaper to just design them to be equivalent.

Car manufacturers prey on this because, as you can see here, probably 95%+ of car buyers don't have the slightest clue about how brake bias works and thus assume that rear discs will stop the car faster. Like I said earlier, I much prefer working on discs, but if you're looking at $700 to upgrade when Ford probably pays less than a $100 premium at wholesale (I'm speculating but you get the idea) to install discs instead of drums, well, you can probably have your rear drums and shoes replaced professionally 2 or 3 times for that price, and your car likely will stop just as quickly as the rear disc vehicle.

If you truly care about emergency stopping distance, then take your $700 and put it toward a better, wider set of tires.
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