New pads, old rotors?

[Rupert]

That does nothing to invalidate the brake feel claim. Try again.

Not sure why some of you guys are on a witch hunt here.

OK, they didn't support their brake feel claim with... anything. Same error you've been making in this entire thread.

[Rupert]

Prove me wrong.

Nah, I'll let that one go. However, lack of appropriate testing means one should be even more cautious and skeptical of claims of improvement, not that one should just believe the inadequate information that is available.

[CaminoRacer]

Let's see, assuming those numbers are correct  0.1346 cc is about 2.5 drops of fluid, not a large amount by any accounting.  How many CCs of brake fluid are displaced when one steps on the brakes? 

I love that statement concerning quicker response to brake pedal inputs.  If true, how much more quickly will the brakes be applied with SS brake lines; t1/100 or 2/100 of a second at the most?  I assume it matters most when you have a situation when you really need to stand on the brakes.  Those times translate into 1 or 2 feet of travel at 70 MPH.  Better tires would have a much larger impact.

A problem that has manifested itself with the braided SS brake lines hasn't yet been mentioned here.  There have been numerous cases of very small grit working through the braid and abrading the Teflon inner line.  Added to that is the problem of the braid covered line continues to look sound while it may be deteriorating while conventional flexible brake line shows outward signs of deterioration.


Some other thoughts:

1.  The people touting the virtues are mainly the people selling the product.   On most car forums I've looked at the jury is still out.

2.  Porsche, to the best of my knowledge use rubber flex lines on their racing applications.  You'd have to ask them why, but I suspect the reason has nothing to do with cost.

Good thing majority of quality SS lines have a clear plastic covering over the braid. Like mine do.

[GoCougs]

Didn't I already tell you to GTFO of here with your OEM BS?

Mass produced street cars aren't going to use SS for a variety of reasons, mostly revolving around cost and the scale of production. They also don't use SS hard line. OEM is NOT the king of performance, like you so foolishly believe.

Why do all major types of racing use SS?

So the GT3, GTR and F458 have concerns with cost and scaling production, whereas a college student working on the brakes of a ~45-year-old car does not?

997 GT3:


GTR R35:


F458:


Your fundamental error is mistaking design for engineering.

[GoCougs]

Buncha smart salesmen who know their audience. Notice that their number one reason is looks. 

How many brake systems (let alone cars) does Summit Racing design?

[Rupert]

Exactly, and it's a good thing too, if that guy is representative.

[CaminoRacer]

Why do F1 cars use SS?

[Rupert]

Do you imagine your car to be similar to an F1 car?

[giant_mtb]

Jesus cripes this is entertaining. 

[CaminoRacer]

Do you imagine your car to be similar to an F1 car?

Engineering is engineering.

[giant_mtb]

Engineering is engineering.

SS lines are some of the last tech to finally trickle down!  Maybe. Some day.

[Rupert]

Engineering is engineering.

Engineering is different for different needs.

[12,000 RPM]

Camino u mite have to take the L on this one bro

[Cookie Monster]

So much arguing over $150 lines.

Sporty, your car, your money. At least it's not going to make your braking performance worse (I hope ).

[GoCougs]

Let's see, assuming those numbers are correct  0.1346 cc is about 2.5 drops of fluid, not a large amount by any accounting.  How many CCs of brake fluid are displaced when one steps on the brakes? 

Yes, let's use their numbers  .

The average brake line seems to be ~0.125 in diameter, the average pad displacement seems to be ~0.25 in and the average hi-po brake system (Corvette, Camaro SS, Mustang GT, etc.) has 4 piston calipers...

The total amount of fluid displaced during full brake application is brake line cross section area * 0.25 in pad displacement * 4 pistons = pi * (0.125 in/2*2.54 cm/in)^2 * 0.25 in * 2.54 cm/in * 4 pistons = 0.201 cc of displaced fluid.

The total amount of expansion during full brake application is 0.1346 cc/ft @1000 psi * 1 ft/12 in * 0.25 in pad displacement = 0.0028 cc of expansion (note: a bit of Googling shows 1000 psi is about right for max brake system pressure).

The total % of expansion = 0.0028/0.201 = 1.4%.

As we know, there is mechanical advantage between brake pedal displacement and brake piston displacement; say 3 in pedal travel = 0.25 in pad displacement. If we take our 1.4% expansion and apply that to 3 in of pedal travel (not sure if it's exactly representative, but it's in the ballpark) we have 0.042 in or roughly a bit less than the thickness of a dime (0.053 in). Now add in relatively blunt vacuum assist, flex in calipers, heat in fluid and pads, even just the soles on shoes, etc., etc., and without a significantly more detailed analysis or case study, no one is going to convince me that factory "rubber" brake line flex is a factor for any driver of any factory car (ergo the use of "rubber" brake lines in $250,000+ ultra high performance cars).

This is probably not entirely right but it proves a point IMO - sure there is some "expansion" but it's lost in the noise of a bunch of other things that are going on.

[CaminoRacer]

So much arguing over $150 lines.

Sporty, your car, your money. At least it's not going to make your braking performance worse (I hope ).

The ability of this forum to make an argument out of nothing is amazing sometimes.

[CaminoRacer]

Why do F1 cars use SS?

Cougs?

[GoCougs]

Yes, let's use their numbers  .

The average brake line seems to be ~0.125 in diameter, the average pad displacement seems to be ~0.25 in and the average hi-po brake system (Corvette, Camaro SS, Mustang GT, etc.) has 4 piston calipers...

The total amount of fluid displaced during full brake application is brake line cross section area * 0.25 in pad displacement * 4 pistons = pi * (0.125 in/2*2.54 cm/in)^2 * 0.25 in * 2.54 cm/in * 4 pistons = 0.201 cc of displaced fluid.

The total amount of expansion during full brake application is 0.1346 cc/ft @1000 psi * 1 ft/12 in * 0.25 in pad displacement = 0.0028 cc of expansion (note: a bit of Googling shows 1000 psi is about right for max brake system pressure).

The total % of expansion = 0.0028/0.201 = 1.4%.

As we know, there is mechanical advantage between brake pedal displacement and brake piston displacement; say 3 in pedal travel = 0.25 in pad displacement. If we take our 1.4% expansion and apply that to 3 in of pedal travel (not sure if it's exactly representative, but it's in the ballpark) we have 0.042 in or roughly a bit less than the thickness of a dime (0.053 in). Now add in relatively blunt vacuum assist, flex in calipers, heat in fluid and pads, even just the soles on shoes, etc., etc., and without a significantly more detailed analysis or case study, no one is going to convince me that factory "rubber" brake line flex is a factor for any driver of any factory car (ergo the use of "rubber" brake lines in $250,000+ ultra high performance cars).

This is probably not entirely right but it proves a point IMO - sure there is some "expansion" but it's lost in the noise of a bunch of other things that are going on.

^ Thinking about it I don't think this is very correct. The entire flex line will see 1000 psi not just the 0.25 in displacement, but that doesn't wash either, because that nets 0.1346 cc for a foot of flex line which would equate to ~67% expansion (0.1346/0.201) or ~2" of pedal mush. Heck with it; all I know is there was any performance benefit $50k Camaros, $100k GTRs, and $250k Ferraris would have SS flex lines from the factory (and they do not).

[GoCougs]

Cougs?

I don't know, but I do know as much that the brake lines on a $5MM+ F1 car are not even remotely related to anything you can buy at Jegs or Summit or w/e.

[Eye of the Tiger]

Fuck this shit. I'm going with electric brakes. SS braided wires.

[280Z Turbo]

I don't know, but I do know as much that the brake lines on a $5MM+ F1 car are not even remotely related to anything you can buy at Jegs or Summit or w/e.

They're...brake lines. Are they made out of T-Rex bones? Unicorn penis?

[Rupert]

T Rex penis.

[12,000 RPM]

I think I am going to pass on the lines.

[giant_mtb]

I think I am going to pass on the lines.

AFTER ALL THIS?!

[CaminoRacer]

AFTER ALL THIS?!

Not ricey enough - have to be under the car to notice it.

[Soup DeVille]

Yes, let's use their numbers  .

The average brake line seems to be ~0.125 in diameter, the average pad displacement seems to be ~0.25 in and the average hi-po brake system (Corvette, Camaro SS, Mustang GT, etc.) has 4 piston calipers...

The total amount of fluid displaced during full brake application is brake line cross section area * 0.25 in pad displacement * 4 pistons = pi * (0.125 in/2*2.54 cm/in)^2 * 0.25 in * 2.54 cm/in * 4 pistons = 0.201 cc of displaced fluid.

The total amount of expansion during full brake application is 0.1346 cc/ft @1000 psi * 1 ft/12 in * 0.25 in pad displacement = 0.0028 cc of expansion (note: a bit of Googling shows 1000 psi is about right for max brake system pressure).

The total % of expansion = 0.0028/0.201 = 1.4%.

As we know, there is mechanical advantage between brake pedal displacement and brake piston displacement; say 3 in pedal travel = 0.25 in pad displacement. If we take our 1.4% expansion and apply that to 3 in of pedal travel (not sure if it's exactly representative, but it's in the ballpark) we have 0.042 in or roughly a bit less than the thickness of a dime (0.053 in). Now add in relatively blunt vacuum assist, flex in calipers, heat in fluid and pads, even just the soles on shoes, etc., etc., and without a significantly more detailed analysis or case study, no one is going to convince me that factory "rubber" brake line flex is a factor for any driver of any factory car (ergo the use of "rubber" brake lines in $250,000+ ultra high performance cars).

This is probably not entirely right but it proves a point IMO - sure there is some "expansion" but it's lost in the noise of a bunch of other things that are going on.

1/4" of brake pad travel would be huge.

But anyways; there's a difference in brake feel. Some people like it, some don't.

[S204STi]

I wanna get new, more aggressive pads.... can I keep my rotors? They don't judder. I wanna change my fluid and get SS lines too. Is DOT 5 too much for the street?

Yes, you can use your old rotors, and don't use DOT 5 for any reason. DOT 5.1, however, you can use.