Brake Kit Marketing 101

[BA.]

I may open a small can o' worms here, but that's ok. I'll just ask you to keep an open mind while reading this.


I'm VERY curious why no brake kit manufacturer/reseller is marketing Brake Kits based upon *stopping distance*. I mean, seriously, that's what most of us are after right?

We're building our cars to perform and for a lot of us, our only point of view is magazine tested stopping distances and how we feel our own cars stop. So, If I drive a 92 Mustang, and the magazine says the car stops 60-0 in about 155', then that becomes my point of reference for all the quoted braking distances I read about.

If I see other peoples built cars stopping in 125', 119 or 109'. I can summize to a point that my own car would need serious upgrading to get to that level of braking, but I don't know what to buy!

I think kits should be rated in small, general terms so that the average Joe can get an idea of what to expect from his purchase.
For example:

Brake Kit 1: 3500lbs - 3900lbs, 235-245 size tires - AA rated traction, Performance tires.
Kit includes: 12" rotors, 1.125" thick, standard pads.
Stopping distance on Highway-quality road: 135' - 150'

Brake Kit 2: 3100-3499lbs, 225 - 245 size tires - AA rated traction, High Performance tires.
Kit includes: 13" rotors, 1.125" thick, Upgraded pads
Stopping distance on Highway-quality roads: 117' - 130'.

I'm sure y'all get the point. I've purposely not listed all variables to keep this somewhat short.
Trust me, when I go to spend my money, I'll be asking the brake companies this. It might be the company with the best answer that gets *my* money.

Teflon applied, let'er rip.

[silver69camaro]

IMO, there are too many variables to standardize the test. Driver ability plays a big role, and that wont be the same from person to person. ABS would solve that problem, however. Also, I don't know if you've ever done braking tests, but the figures can vary by several feet each run. But anyway, I wouldn't choose a brake company just off of those figures. I would be more concerned with their repuation with the track crowd; I think this says more than braking distance, which in my opinion, is like horsepower. It's just a number, and it only tells a small part of the whole story.

Honestly, most brake kits would fall into the same 15' distance span. Repeated stops would be a good test metric as well, but I don't know how you'd attach a numerical value to brake fade.

[6'9"Witha69]

I agree with silver69, repeatability is key versus 2 or 3 short stops. I don't care how my car stops the first 3 times in a day, but how it handles repeated stops from both high and low speeds in rapid succession.

[protour_chevelle]

WAY too many variables.

-Matt

[DeepBlue68]

Honestly, most brake kits would fall into the same 15' distance span. Repeated stops would be a good test metric as well, but I don't know how you'd attach a numerical value to brake fade.

That would be pretty cool to have a standardized test to quantify brake fade. You could have cars tested on a straight, flat road with "controlled" conditions (as much as possible, anyway), and do repeated stops at different levels of pedal input and watch the stopping distance start to creep up with as the tests continue. I guess you could do it on a track, but it would have to be the same track for every time for the results to mean anything. And it'd have to be the same driver too. Ahhh, crap, as others have said, there's probably way too many variables to be able to have any kind of practical standard that means anything, but it would be kinda cool.

[Mkelcy]

I can hear lawyers' ears perking up everywhere as they consider the potential lawsuits based on a car stopping 10 (or 20 or 30) feet farther than it should have gone. The potential liability for claiming a given stopping distance is simply too great.

[BA.]

Oh well, at least we got 120+ reads on the thread in one night!
I don't think I got my point across very well though.

My thoughts about the 'variables' are that the point is to LIMIT the variables. I wasn't thinking of an ASA standard, just something within a company like Baer or Wilwood or Stoptech or SSBC. If they all use similar standards, great, if not, AT LEAST I can compare what I get for my money with differences from 12" to 14" rotors, etc.

We're NOT trying to compare driver 'A' to driver 'B', or car 'A' to car 'B'. That would be silly.
In the end, there are truly only a handful of variables that make a large difference in the braking and those could be mostly standardized within a company.

As Silver69 mentioned, even back to back tests can vary slightly, but THAT'S one of the reasons my example uses a range. No one should expect exact duplication of a test, and the range helps to bring that point home as well.

I DO like the mention of repeatability because that is really an important factor. In fact, it's a huge reason a friend didn't like the brakes on his C5 Vette.

One final thought. When we buy an aluminum head for a motor, what two things do we look for? Horsepower tests and Flow right?
batteries have cranking amps.
Cams are tested for HP gains, the variables there are MORE than for braking.

What do ya got for braking systems? Bupkus I tell ya. Bupkus.

[silver69camaro]

I agree, but cams are incorrectly marketed for thier power gains, when really it's all about torque curves and where the power is made...so like you said, same deal with brakes.

Now, the way I see it, you could measure a brakes true ability by using a "brake dyno", where the energy input is correlated against energy output in the form of heat (delta T). I guess this can provide a back-to-back comparison between brake designs, but still doesn't measure the caliper's ability to resist flexing. In the end, I'd say on-vehicle testing is a no-no.

Something to think about: What information are you really looking for? If you're trying to compare 12" against 14" rotors, well you don't need a brake dyno for that...just do the math. How about piston sizes? That can be figured mathematically also. IMO, the data that I'd want to know is caliper flex, pad taper, etc...again, all of which can't easily be measured or compared...and all of which are good benchmarks for brake system design.

[chicane67]

The most left out items of discussion in things such as this..... ??

BIAS, COG movement and tires.

If you look on the "real" tuner sites, they actually use the stopping distance... with what they specialize in. Becasue of the variables, that is where manufacturers have to draw the line in advertising as not to mislead the end user. Case in point, BAER ran into this. They were using "this" point in their early marketing but some of the end users didnt feel that they were getting what was advertised, and that makes sense. If the end user doesnt educate themselves to what it does take to get 'those' numbers, then they lay blame on the manufacturer and or installer.

One example of what you have proposed, Doug Rippie Motorsports. Ole Dougiepoo gives you a good approximate of what to actually expect... with a specific chassis using a few different systems, right up to the high end APRacing system... in which he leaves you to question, "Wow, wonder what them things there do." I can tell you, that their APRacing system is under 100 feet... quite a few under, if the bais and COG is managed correctly and the end user understands threshold braking.

I would go to say that most of the higher end systems are in a 30.. foot distance span, vice the 15 foot span mentioned earlier. There is much to be gained when you step up to the higher end systems if you have such requirements.

The real question is... do you really need that or will you ever utilize that system to its potential ?? Maybe yes, most likely no.

And on one final note... its the tire that stops the chassis, not the brakes.

[andrewb70]

The most left out items of discussion in things such as this..... ??

BIAS, COG movement and tires.

If you look on the "real" tuner sites, they actually use the stopping distance... with what they specialize in. Becasue of the variables, that is where manufacturers have to draw the line in advertising as not to mislead the end user. Case in point, BAER ran into this. They were using "this" point in their early marketing but some of the end users didnt feel that they were getting what was advertised, and that makes sense. If the end user doesnt educate themselves to what it does take to get 'those' numbers, then they lay blame on the manufacturer and or installer.

One example of what you have proposed, Doug Rippie Motorsports. Ole Dougiepoo gives you a good approximate of what to actually expect... with a specific chassis using a few different systems, right up to the high end APRacing system... in which he leaves you to question, "Wow, wonder what them things there do." I can tell you, that their APRacing system is under 100 feet... quite a few under, if the bais and COG is managed correctly and the end user understands threshold braking.

I would go to say that most of the higher end systems are in a 30.. foot distance span, vice the 15 foot span mentioned earlier. There is much to be gained when you step up to the higher end systems if you have such requirements.

The real question is... do you really need that or will you ever utilize that system to its potential ?? Maybe yes, most likely no.

And on one final note... its the tire that stops the chassis, not the brakes.

So basically a bad ass APRacing system will restore your Camaros braking system back to stock 4 wheel drum like performance when used with 20 inch wheels.

<<<Putting the fire suit on>>>

Andrew

[Skip Fix]

I'm sorry I do somewhat agree with BA. They should be able to show their system is better than stock or others, not just based on theory or advertising BS in magazines. Magazine articles are a little suspect also. They are not "peer reviewed" like engineering or scientific articles generally are. They often do have a slant as to who spends the most advertising dollars with the magazine. Example a few years back my machinist build a Pontiac motor that appeared in Muscle Car Review. Motor had an Ultradyne cam, article stated Comp! Many other similar changes.

Some of it gets into brake system design, but I think more is marketing BS.

The variables as I see rotor diameter as a factor to keep constant.Thickness I can give them I don't think most of us would see a 1.00 vs a 1.25 and measure it. Let's maybe assume a 12" rotor we can get a factory 1LE or Baer with them. Not just a big rotor for appearance in big wheels, use a standard sized one.

Many companies have rating of calipers based on sq in of piston(s). Line pressure PSI over more sq in should provide better clamping. So why are Baer with smaller two pistons SQ IN better than a stock second gen with one big single? Do 2 pistons REALLY clamp better on the pad than a single? How do you measure it? "If you can't measure it it isn;t real" is an old engineering saying. Are 4 pistons then not better than 2?

Pad size can be a factor and often isn't even addressed or mentioned. The larger a pad the more surface area for friction and also can cool better.

So on a standard weight 3700 lbs second Gen F body stop better with a factory TA type 4WD, Baer 2 piston front caliper system, Wilwood HD street 10.75 rotor 4 piston front and rear???

The Wilwood standard system use a 4 piston caliper that has an awful small pad, but ALOT of drag cars use them, but they don't have repeatable stops to worry about fade.

[BA.]

A "brake dyno" - now that sounds cool. I can almost envision it too. How great would that be if a standard input speed or torque were used and then the rotor heat output measured by infra-red or something?(or temp. measurement after a specific time factor) It'd be a nice way to measure a rotors ability to dissipate heat over 2-3 runs and compare to someone elses rotor.


I didn't realize that Rippie does what you mentioned Chicane, but you're right, that is ideally what I think would be nice to see (at least) from within one company like Bear or Wilwood or SSBC. A comparison of real performance data about each package, or how it changes between packages.

When you mentioned this:
"If the end user doesnt educate themselves to what it does take to get 'those' numbers, then they lay blame on the manufacturer and or installer", ,....my eyes lit up because it's SO SO true, but then again, something I would never do myself. And because it's true, I'll probably never see the data from Bear or Stoptech or SSBC that I want to.

Thanks for your input guys!


MKELCY: "disclaimer" my friend. That's all it takes. But you are right, some idiot somewhere would try to take advantage. Then again, we don't see Camshaft and Head manufacturers getting sued, or K&N getting sued because Product X didn't give them "10-15" horsepower. (K&N's an easy target there)

[terryr]

Who would do the testing? Who would install the kits?

Companies would just lie and say 100 feet, 90 feet 80 feet.....

If the kit didn't do it they would blame the installation.

Besides, no one else 'guarantees performance'. They might say "up to 40 horsepower", or "as much as 10 % better", but that's it.

[chicane67]

So basically a bad ass APRacing system will restore your Camaros braking system back to stock 4 wheel drum like performance when used with 20 inch wheels.

<<<Putting the fire suit on>>>

Andrew

Uhm... no.

What would give you that impression ?? Feeling a little today Andrew ??

[ks71z28]

So then we create a forum like this to discuss and compare our mods, hey since where here.

My set ups

Baseline- 1968 Firebird 3200 lbs, Tires Bfg TA 225/60/15. front stock sigle piston 11" rotors, rear drum. Stopped every time at 150' from 60mph, like clockwork. Test used cones and measuring tape, and G-tech Pro RR

71 Z28 3550lbs. Tires Kuhmo Mx 275/40/18- Front 12" B-body rotors, Willwood GMiii single piston calipers, rear 78 Cady Seville 11" discs, Hawk HPS pads. Stopped 130-135' from 60 mph.

By the way the road had some dust on it, and I flat spotted the front tires (ouch!)

I would like to see some numbers of a c5 13" set up on a 2nd gen.

[andrewb70]

Uhm... no.

Feeling a little today Andrew ??

Yes...



Andrew

[ks71z28]

So what no one has any numbers, I have found from racing that seat of the pants numbers aren't good ways to quantify changes. Please share you brake systems and any actual useful data you have regarding the set up. This is the best use of this forum, and thanks

Keith

[chicane67]

So what, no one has any numbers? Please share you brake systems and any actual useful data you have regarding the set up.

Well, my 67 had factory four piston fronts with drum rears. At the time, it weighed in at around 3200lbs with 14x7 wheel, a 235/60/14 BFG Radial T/A tire with a WS6 power master, set up as a manual application. Here is the low down:

Front:
Brake manufacturer: GM Delco Morrane
Caliper/Piston Number: D3 four piston; 1 7/8" dia
Rotor Manufacturer: Classic
Rotor Type: Solid 1 pc integral hub
Rotor Dimensions: 11 x 1"
Wheel/Tire Size: 14x7 235/60/14
Tire make/model: BFG Radial T/A
Brake Line: Mildsteel 3/16" hardline, Guldstrand SS Flex lines
Brake Fluid: Wilwood 570
Pad type/compound: Porterfield R4-S
Master size: 1 1/8"
Weight: Unknown
Combined left and right: Unknown

Rear:
Brake Manufacturer: GM Delco Morrane
Drum: Stock
Drum Manufacturer: GM
Drum Type: Solid, iron, non drilled/vented
Drum Dimensions: 9 1/2 x 2 1/4"
Wheel/Tire Size: 15 x 8 255/60/15 BFG Radial T/A
Tire make/model: BFGoodrich g-Force T/A KD
Brake Line: Mildsteel 1/4" hard line, Guldstrand SS Flex line
Brake Fluid: Wilwood 570
Shoe type/compound: Porterfield R4-S
Master size: 1 1/8"
Weight: Unknown
Combined left and right: Unknown

After a long stint of testing with Andy Porterfield, while working for Guldstrand, I found and stayed with his R4-S compound. It was what the chassis liked the best. In the noted above trim, I got it's 60-0 down to roughly 118ft in the dusty lane at Streets of Willow and backed that up multiple times at various autoX events in the dust bowl of Jack Murphy Stadium with the average stopping in the 118-120ft range. It didnt really have anything exotic done to it, but I did run the rear shoes backwards to change the effective rear bias and I ran my 720/320 spring package which did tweak the rear IC and nulled any brake hop/axle tramp on decel.

I was then the first person to get BAER's 13" PBR Track system into a 16" wheel. It used Vintage Wheel Works "V45"s a 3/16" spacer which was only needed when the pads were new... but I never got any numbers from that system. We'll have to ask Carl and/or John if they have any numbers as they did this same system a few years later and I know Carl has a bunch of track time to give us a good impression of how that system actually works.

The new system is a little different. Its on the other end of the spectrum, the chassis is much lighter and many other things have been tuned/dialed beyond what I had to ability to tune in the last system. Not to mention the 38 channel Advantage data acqusition... Ill have all the data one could want.

Front:
Brake Manufacturer: AP Racing
Caliper/Piston Number: CP5555, differential bore six-piston
Rotor Manufacturer: AP Racing
Rotor Type: Slotted 2 pc, McLaren floaters
Rotor Dimensions: 355mm x 35.5mm (14 x 1.4")
Wheel/Tire Size: 18x9.5 265/40/18
Tire make/model: BFGoodrich g-Force T/A KD
Brake Line: Stainless 3/16" hardline, Goodridge SS Flex lines
Brake Fluid: Motul RBF 600
Pad type/compound: Ferodo 2500
Master size: 7/8"
Weight: 33.5 lbs
Combined left and right: 67 lbs

Rear:
Brake Manufacturer: AP Racing
Caliper/Piston Number: CP5147, four-piston
Rotor Manufacturer: AP Racing
Rotor Type: Slotted 2 pc, Steel hat, factory e-brake compatible
Rotor Dimensions: 330mm x 25.5mm (13 x 1")
Wheel/Tire Size: 18x9.5 275/40/18
Tire make/model: BFGoodrich g-Force T/A KD
Brake Line: Stainless 3/16" hard line, Goodridge SS Flex lines
Brake Fluid: Motul RBF 600
Pad type/compound: Pagid RS421
Master size: 1"
Weight: 27.5 lbs
Combined left and right: 55 lbs

This is the Holy Grail of brake systems.

I have installed and used various systems from every manufacturer..... (Alcon, AP Racing, Brembo, CNC, PBR, Perf Fric, JFZ, Stoptech and Wilwood) which also goes for pad/compounds (Axxis, Carbotech, Ferodo, Hawk, Pagid, Perf Fric, Porterfield, Poly Matrix, Raybestos and Mintex). The modulation, fade resistance, predictability and shear stopping power of these independant systems is nothing short of phenomenal.

When dialed in, Ill be looking at sub 95' (or better) 60-0 stopping distances.

[Steve1968LS2]

IMO, there are too many variables to standardize the test.

This is the reason.. too many factors

Tire size
Road surface
Tire compound
Testing method
Vehicle weight and even suspension stiffness
Pad type
Pad condition
Pad temp
etc