Big brake question ... 911 tt calipers vs Boxster calipers

[QuattroRocket]

I am looking at braking solutions for the Spring and ECS has a few types of Porsche upgrade kits available. As the Stoptech/Alcon type solutions will blow my budget the Porsche caliper option is starting to look like the best/only choice.

Now the stage 4 kit is out as I am real sure it wont clear my summer wheels and it absolutely wont clear my 17" winters. So its down to the stage 2 v2.0 kit with Boxster calipers at 332mm or the Stage 3 kit with 911 tt calipers at 322mm but with slightly less clearance.

I will determine if both kits clear my wheels shortly but I am wondering what the real world driving difference would be between them ? Is it one of those 90% improvement over stock versus 95% improvement over stock things where it really doesnt matter or is there a real difference ???

[Papachristou]

no, few people if any truly use their BBK. they are mainly for looks and fade. not stopping distance

[blmlozz]

no, few people if any truly use their BBK. they are mainly for looks and fade. not stopping distance

ditto
If anything, BBK's *increase* stoping distance, which makes them bad for DD.
The advantages that they give are reduced brake fade. For the quickest stoping distance, get some good brake fluid, SS lines and nice pads. Plain jane blank rotors work best even.

To answer the OP's question though, Don't bother with the boxster caliper systems unless you like the OEM support (since it uses the A8 rotors). If you spend that kind of dough on a BBK and don't autocross or some kind of pro racing it's going to be for looks, and the 911 caliper looks better imo.

[absolutegtr]

I doubt you will see a difference between a 332 and 322 kit.

Why not consider a B5S4 "BBK"? I believe it is 321mm and I love mine

[KPC1.8TQuat]

ditto
If anything, BBK's *increase* stoping distance, which makes them bad for DD.

Care to elaborate on that because I had a very different experience.

I went for a ride in my tuner's S4 with Alcons and the braking power was ridiculous. Every time he leaned on the brakes it felt like we were deploying parachutes and settling into slowly thickening cement (if you can imagine that description).

Quite the difference over stock in my opinion.

[J-jizzle]

I doubt you will see a difference between a 332 and 322 kit.

Why not consider a B5S4 "BBK"? I believe it is 321mm and I love mine

I will be putting mine on during winter break. I can't wait because I have had the O shit feeling with these a few to many times when I'm on and off them a-lot.

[absolutegtr]

Care to elaborate on that because I had a very different experience.

I went for a ride in my tuner's S4 with Alcons and the braking power was ridiculous. Every time he leaned on the brakes it felt like we were deploying parachutes and settling into slowly thickening cement (if you can imagine that description).

Quite the difference over stock in my opinion.

Its been proven and discussed already. A BBK will actually hurt the stopping distance.

In the end what limits you is the amount of fluid the master cylinder can push and also the tires only have so much traction

[blmlozz]

Care to elaborate on that because I had a very different experience.

I went for a ride in my tuner's S4 with Alcons and the braking power was ridiculous. Every time he leaned on the brakes it felt like we were deploying parachutes and settling into slowly thickening cement (if you can imagine that description).

Quite the difference over stock in my opinion.

BBK's unevenly distribute the amount of hydraulic pressure required to stop the front and rear rotors. The boxster and 911 calipers require much less pressure to distribute the same amount of stopping force as the OEM calipers, and as such this leaves the rear calipers with less pressure to work with without any increase in stopping amount.
lets just say that it takes 10lbs of force to get 100% stopping force on the front oem calipers and 100% for the rear..
upgrade to bigger calipers without balancing the rear and you get this:
5lbs force for 100% front power and since we don't have as much pressure, we're only getting 50% out of the rear caliper and not stopping the car as quickly as it could. This dosen't even account for the master cylinder on the porsche's having higher pressure to better use the calipers too.

Car manufactures don't just throw brakes on a car.. lots of R&D goes into balancing the braking so that the front and rear are loaded equally and thus stopping the car the most effeiciently.


Your friend has alcon's too.. which to be honest, are not even in the same league with the boxter or 911 upgrades, and if he was smart and had enough cash to get alcons then chances are he did the rears too to compensate.

[KPC1.8TQuat]

So larger rotors, better pads, and upgraded brake lines hurt stopping distance?!

[KPC1.8TQuat]

upgrade to bigger calipers without balancing the rear and you get this:
5lbs force for 100% front power and since we don't have as much pressure, we're only getting 50% out of the rear caliper and not stopping the car as quickly as it could.

Ok, that makes sense now. Thanks.

[blmlozz]

So larger rotors, better pads, and upgraded brake lines hurt stopping distance?!

that alone.. no, when you put oversized calipers on it hurts stopping distance.

[KPC1.8TQuat]

that alone.. no, when you put oversized calipers on it hurts stopping distance.

And do you consider the Porsche Boxster and 911 turbo calipers to be oversized?

Also you are correct, my tuner with the Alcons did his rears too.

[SeKKeY]

Car manufactures don't just throw brakes on a car.. lots of R&D goes into balancing the braking so that the front and rear are loaded equally and thus stopping the car the most effeiciently.

do you agree that the B6 A4 1.8T has UNDERSIZED brakes from the factory?

[[email protected]]

Skip the ECS stuff and get some Stoptechs instead

[blmlozz]

And do you consider the Porsche Boxster and 911 turbo calipers to be oversized?

Also you are correct, my tuner with the Alcons did his rears too.

oversized in relation to a stock rear caliper on the B6? yes, I do.

do you agree that the B6 A4 1.8T has UNDERSIZED brakes from the factory?

that's a bit rhetorical isn't it? Are they undersized for a performance enthusiast that constantly does 100-50 stops? Probaly. Undersized for a middle aged 40 year old that uses his B6 as a daily to work, I don't think so. Anything can be improved upon.. it's when there's an unbalance in the system that messes things up.

you wouldn't go from a 3" dp to your factory exhaust would you? of course not.. because it wouldn't make sense and just choke the system. Same theory.

[QuattroRocket]

So I find myself back looking at the 3.0l upgrade with ss lines or an S4 setup. No st much bling but 1/2 or less cost.

[[email protected]]

If you want to go OEM then skip the 3.0 setup and go with a B7A4 or B6S4 setup.

[dougyfresh]

If you want to go OEM then skip the 3.0 setup and go with a B7A4 or B6S4 setup.

Correct. You'll notice a huge difference.

I noticed a huge difference going to B5 S4 fronts and I have shitty pads installed with OEM rotors.