Brake NEWBS "must read"

[GregWeld]

For anyone that is having brake issues -- or wants to upgrade or modify a brake system... this is a must read IF you don't understand all the nuances of a PROPER braking system.

This is a MULTI PAGE article that will explain every aspect of the system in terms you can understand.

http://www.hotrodheaven.com/tech/brakes/brakes1_index.htm


:thumbsup:

[Ron in SoCal]

Loved that article, Greg. There were formulas in there that I had heard of but never knew how to calculate. Thanks for posting...

[Jano4]

Good article. Fairly straight to the point.

[nullshine]

Removed.

[Apogee]

...So, am I missing something extremely important in the design of the dual masters, or what??? Am I misunderstanding what he is saying???

James,

Your math is correct and yes, the laws of thermodynamics are still in play last I checked. You're not missing anything from what I can tell...that article states numerous things that are at best misleading and/or arguably abiguous, or at worst just plain incorrect. I'm not trying to bash the article, just help those who may be looking to educate themselves, as brakes are a very important subsystem of any vehicle.

The real reason tandem master cylinders were made mandatory in the mid-60's by the government regulating bodies isn't even stated (safety???), so I'd suggest taking everything with a grain of salt. We could pick apart the article paragraph by paragraph, but really what would be the point? Your time would be better spent reading "High-Performance Brake Systems: Design, Selection & Insatallation" by James Walker Jr, "Brake Systems: OEM & Racing Brake Technology" by Mike Mavrigian & Larry Carley, and "Brake Handbook" by Fred Puhn...all oldies but relatively goodies IMHO. At least they don't contain massive amounts of misinformation. While the article could be considered informative to some, I would suggest sticking to higher-level resources including articles and books written by experts in the braking field (e.g. Stoptech White Papers).

Tobin
KORE3

[GregWeld]

The article that was posted was for NEWBS -- as stated in the headline -- and was intended to answer some very basic questions that get asked over and over... while it's not the ultimate brake tech paper... it is certainly worth reading and would/will go a very long way to help a NEWB get started and to ask the correct questions and get some results and basic understanding.

I agree Tobin - that if you REALLY want to stop and be PT level car - there is MUCH MUCH more to be learned.... but that wasn't the intended post here.

[nullshine]

First and foremost I must stress that no disrespect is meant here.

However, I strongly disagree that this article is a must read for newbs. This article will only serve to confuse, even though it is fairly inclusive and straight forward, there are statements which I am sure are incorrect.

I am no brake or physics guru, make no mistake. However, I do have a background in fairly basic hydraulic systems, and the information that i previously quoted the author on, regarding the hydraulic aspects, I know to be incorrect.

As a brake/physics newb myself, I found myself confused at several points in that article (due to my general knowledge of hydraulics, and rudimentary knowledge of physics), and questioning the validity of many of the statements within it.

However, I offer an alternative, perhaps this power point presentation might serve as such. I've read through it, and I am unable to recognize any misinformation in it. While it doesn't delve into rotor or caliper types or mechanics, I think it does contain a lot of information that is necessary to understanding the basics of braking. Some of the formulas may be over the head of a newb, but there's still a lot of usable info there.

One thing I don't understand is why the force of the booster isn't included in the braking torque formula, but I'm thinking they're just simplifying it as a manual braking system by removing the force of the booster from the equation. (Frame 9)

www.sae.org/students/presentations/brakes.ppt

Anyways, hopefully this link doesn't contain any misinformation that I'm unaware of, or unable to recognize.

[JRouche]

Ok. I read the info from the link. It does have alot of info for a guy that is new to brakes. Say he hasnt done any researching on the net or read any books.

Nice summary for that person. But it reads kinda odd. Like a person that picked out some key points from various articles and books. Like he isint speaking from knowledge or experience. But more from bits and pieces he has read about.

Kinda like if I were to write a paper about the basics of automobile brakes. I for one dont know squat about brakes. But I can regurgitate what I have read. And I do that way too much!! Bad on me. But after reading that paper I saw a lil of my own writing style in there. Regurgitating info I have read about and dont really have any real world expertise. Makes me kinda embarrassed now. I saw a reflection of some of the stuff I talk about. And its filled with holes and some mis-information...

Kudos to the guy that wrote the paper. It is a decent, very decent guide for some of the workings of the braking system. Some of the technical issues are prolly over looked, or over simplified and incorrect. But most of the raw info is a good insight for the new guy looking at his braking system.

Kinda an eye opener for me to be honest. I tend to regurgitate some of the reading I have done and post it as what I know. Far from the truth. I gotta stop adding opinion and start listening more... Errrr!!!

But anyway. Yup, nice read for the guy that wants to get a deeper grasp on the brakes in his car. For a more technical description there are some great books out there. JR

[GregWeld]

JR --

That was the "original intent" of my posting of the article.... and I ALL CAPS the NEWBS part for that very reason. It is a "starter primer" for someone that just hasn't a clue about all of this.... and they can start to get a grasp. Want to go deeper - now you can jump off from here and get into the subject.

Personally -- if anyone read this article -- they'd have a "decent" brake system if they followed the basic rules set out. Pressure / MC sizing / Pedal ratio / line choice etc.

Some times I get into a subject - read an article like this - as a newb to the matter at hand - and realize that maybe I should seek out a professional for the job... so if that helps someone come to that realization... then GREAT! Because BRAKES are kinda important... maybe a whole lot more important than header tube size even.... :rofl:

[GregWeld]

@NIN

The side by side dual MC has a significant difference over a dual inline MC.... because of two rather simple reasons...

The side by side version uses a BALANCE BAR to adjust the bias. So the SBS system can use a smaller bore making more pressure and stroke is VERY IMPORTANT... to the overall feel of the system.

For comparison sake - a 1" bore MC will give the same brake system a "hard pedal" --- while a 7/8" MC will have a "softer pedal".... BOTH will be adequate to stop a big brake car... so NOW we're discussing the FEEL of the pedal rather than the most mathematically correct version. The 1" will need more "input" than the 7/8 in order to apply the same pressure... but they'll both be fine depending on the feel you want. A NEWB would not know this -- and might be real unhappy going from a Pwr/B system to their new big brake manual system and then discover the 'effort' and feel isn't what they wanted/expected (I find this the MOST COMMON issue). Had they gone to a 7/8 - they'd have been happier (less effort - more stroke). Unfortunately the article (if I can remember) doesn't address that kind of info and a newd wouldn't get that out of doing the "math". But that's why we need experts like Tobin at Kore3 and Wilwood and Baer...

However - if they read the article and did the math -- they (the newb) most likely would have chosen the smaller bore MC and ended up with a system that was plenty adequate given all the other parts were also chosen correctly. How many guys do you know - do a small block chevy and then ASSume that a 750 cfm carb is the best choice - because that's what everyone else is running.... THEY have no clue that there may be some simple math they could have done that would have pointed them to a 650 and the overall 'system' would have performed better had they learned the simple rules....

That is why the article is for NEWBS and is a starting point for some very basic information that gets asked here - and in every other forum constantly... it will answer some questions.

[ccracin]

Go back to your "Shed" and build a test rig. I want PROOF! I'm a NEWB and I'm completely confused. I hope you're happy! :_paranoid :unibrow:

[nullshine]

Removed.

[GregWeld]

Go back to your "Shed" and build a test rig. I want PROOF! I'm a NEWB and I'm completely confused. I hope you're happy! :_paranoid :unibrow:

Chad -- I was going to build a complete M/C test station - and have it on display at all the GG shows... imagine if you could sit in a seat - grab a steering wheel and actually COMPARE various M/C (say all the various Wilwoods) and see a gauge in front of you with the PRESSURE you're making at the calipers... that way you could actually equate the pedal feel - to the clamping pressure.

But sadly - for YOU (grin) - I'm really busy helping my ASU senior do a rough draft on the comparative cooling in the noon day sun of a fresh Chihuahua dump vs a Newfoundland... and am just flat out of time. :rofl:

[GregWeld]

@ NIN --- JAMES.... :D

A question like that should be asked of the various manufactures -- and they all have tech help. I am not an engineer and have no knowledge of the workings of one M/C over another.

I've helped fix many of my buddies "messes" (I'm mostly a hot rodder - and hot rodders have more bad info in their heads than good!)... And when I'm doing my own cars (too many builds to count - like north of 30) or helping a friend - I just try to stick to the basics... bore - pedal ratio - lines... and we usually end up happier.

Funny statement that comes up all the time - especially with "newbs".

I put disc brakes up front and I have a power booster - but I'm not really "impressed" with them.... Maybe I'll put on one of those dual 8" boosters...

I ask what they don't "like" about the new system -- and they usually don't like the pedal feel. So we'll start with the basics... as in -- how much vacuum they're pulling - what MC is being used - what's their pedal ratio. For a newb -- there's little point in going into a bunch of techno discussion.

On Lat G and other sites -- there's LOTS and LOTS of technical discussions about pads - and pad knockback - and bias adjustments - and caliper stiffness - and rotor size...

Funny though --- nobody ever buys a simple pressure gauge kit to see what pressure they're actually making... a kit can be bought for like $45.

[ccracin]

Chad -- I was going to build a complete M/C test station - and have it on display at all the GG shows... imagine if you could sit in a seat - grab a steering wheel and actually COMPARE various M/C (say all the various Wilwoods) and see a gauge in front of you with the PRESSURE you're making at the calipers... that way you could actually equate the pedal feel - to the clamping pressure.

But sadly - for YOU (grin) - I'm really busy helping my ASU senior do a rough draft on the comparative cooling in the noon day sun of a fresh Chihuahua dump vs a Newfoundland... and am just flat out of time. :rofl:

You guys are behind out there. My 5 year old twins did that paper last week! We also calculated the methane production over time! :faint:

Actually I thought the brake pressure gauge on a comparative setup would be great. I think Wilwood and Baer should jump on this. Good article as long as people do as they should with all things and take all in moderation. :cheers:

[GregWeld]

Forgot the thread is for "newbs" ---

The pressure gauge can be screwed into the BLEED screw... after you remove the bleed screw - you install an ADAPTOR (various for various calipers) and have a short piece of flex hose with a gauge on the end of it.

SSBC sells a kit like this for about $50 or so.

I'm sure you can spend a little or a lot on "pro" gauge sets. Just google or check Jegs or Summit etc.

[ccracin]

@ NIN --- JAMES.... :D

A question like that should be asked of the various manufactures -- and they all have tech help. I am not an engineer and have no knowledge of the workings of one M/C over another.

I've helped fix many of my buddies "messes" (I'm mostly a hot rodder - and hot rodders have more bad info in their heads than good!)... And when I'm doing my own cars (too many builds to count - like north of 30) or helping a friend - I just try to stick to the basics... bore - pedal ratio - lines... and we usually end up happier.

Funny statement that comes up all the time - especially with "newbs".

I put disc brakes up front and I have a power booster - but I'm not really "impressed" with them.... Maybe I'll put on one of those dual 8" boosters...

I ask what they don't "like" about the new system -- and they usually don't like the pedal feel. So we'll start with the basics... as in -- how much vacuum they're pulling - what MC is being used - what's their pedal ratio. For a newb -- there's little point in going into a bunch of techno discussion.

On Lat G and other sites -- there's LOTS and LOTS of technical discussions about pads - and pad knockback - and bias adjustments - and caliper stiffness - and rotor size...

Funny though --- nobody ever buys a simple pressure gauge kit to see what pressure they're actually making... a kit can be bought for like $45.

Look in any top running circle track car and you will find brake pressure gauges. It is an absolute necessity for proper tuning. With them, you don't have to be a braking engineer. You make adjustments record the settings and take a drive. When you get what you like on the street make note of the pressures. Then the same for the track. I support Greg completely with the gauges suggestion. Cheap tuning tool! Also, check Speedway motors. They are hard to beat on this stuff.

[GregWeld]

Chad ---

Alex will get an A+ now! 'Cause I'm going to have him add the section on methane!! THANKS!!
:lol:

Seriously -- the thread was really intended for a guy to read that article and "somewhat" get a handle on all this various info - like bore sizes and what that means etc.

I didn't want to start a "boring" (pun) thread on high tech math and all the various nuances of a bullet proof track style brake system... So I get a bit annoyed when people start with the "well if you jack B into A and deduct the length of a piece of rope...." and the thread goes all over the place...

It was more a "hey" -- if you're interested -- here's a pretty decent article that breaks (pun intended) it all down.... and you can go from there. No biggie. :cheers:

[GregWeld]

Chad ---

SERIOUSLY!!

(quote)Actually I thought the brake pressure gauge on a comparative setup would be great. I think Wilwood and Baer should jump on this. Good article as long as people do as they should with all things and take all in moderation. (end quote)

I'm SHOCKED that they don't have/include a display like this at their shows... especially when they're doing "retail" shows. It could be pretty simple - with maybe a 1 1/8" - a 1" and a 7/8" and a side by side MC/balance bar set up.

4 cheap adjustable seats - 4 cheap wheels - 4 pedals - and 4 LARGE pressure gauges.... you could run these on a two across or link them for 4 side by side... a guy could sit down press the pedal and see what it feels like and what braking he's getting out of it... build it all out of tubing -- and put it on wheels to roll in and out of their trailers. It might save them a HUGE amount of time on educating consumers about all of this stuff. They could also incorporate in the actual build - how lines should be run - prop valve placement (like - to the rears) so they could show the increase or reduction by tuning it... and they could demonstrate proper pedal ratio too and how that affects the pressure made. It would be kinda cool to see 'em build something like that.

[ccracin]

Chad ---

SERIOUSLY!!

(quote)Actually I thought the brake pressure gauge on a comparative setup would be great. I think Wilwood and Baer should jump on this. Good article as long as people do as they should with all things and take all in moderation. (end quote)

I'm SHOCKED that they don't have/include a display like this at their shows... especially when they're doing "retail" shows. It could be pretty simple - with maybe a 1 1/8" - a 1" and a 7/8" and a side by side MC/balance bar set up.

4 cheap adjustable seats - 4 cheap wheels - 4 pedals - and 4 LARGE pressure gauges.... you could run these on a two across or link them for 4 side by side... a guy could sit down press the pedal and see what it feels like and what braking he's getting out of it... build it all out of tubing -- and put it on wheels to roll in and out of their trailers. It might save them a HUGE amount of time on educating consumers about all of this stuff. They could also incorporate in the actual build - how lines should be run - prop valve placement (like - to the rears) so they could show the increase or reduction by tuning it... and they could demonstrate proper pedal ratio too and how that affects the pressure made. It would be kinda cool to see 'em build something like that.

I agree with your previous comments about the read. That's why I tried to lighten the load!:lol:

You know, as for the above. Since I happen to have some modeling and design skills and you happen to have some really cool tools and some time...................hmmmmmmm:unibrow:

In all seriousness if anyone has contacts at either of these places, this is a no brainer.

[Grnova]

Hey Greg I will consider myself a NEWB when it comes to brakes. Do you think you could give me you opinion on my situation. http://www.pro-touring.com/forum/showthread.php?t=67069

[GregWeld]

GR ---

Yep I can help you a lot! Call TOBIN at KORE3

http://www.kore3.com/


Don't take "advice" from a bunch of DB's on a forum... talk to a real expert about what you have and what you are going to need to "fix" it.

My initial advice is that you're running a "hot rod" brake (I have larger calipers and rotors than that on my 37 Ford!) on a car you're trying to "track" --- but even then --- you should be able to lock the brakes up on the street. Period. If you can't then you have something out of whack - which you already seem to know.

[nullshine]

Removed.

[Grnova]

GR ---

Yep I can help you a lot! Call TOBIN at KORE3

http://www.kore3.com/


Don't take "advice" from a bunch of DB's on a forum... talk to a real expert about what you have and what you are going to need to "fix" it.

My initial advice is that you're running a "hot rod" brake (I have larger calipers and rotors than that on my 37 Ford!) on a car you're trying to "track" --- but even then --- you should be able to lock the brakes up on the street. Period. If you can't then you have something out of whack - which you already seem to know.

I did talk to t Wilwood tech guy and he said that I need the 3 factors for good brakes:

1) Good brake pressure 900 to 1000
2) Pedal ratio 6:1
3) friction- which I did not have until today when I installed my new pads...BP20's

The car finally works like I wanted it to These pads are considered a mild race pad but since I am not running drilled or slotted rotors they should last me some time...How long ? don't know yet.
But that is one more thing I can cross off the list.

[GregWeld]

And there ya have it!

Good!

Now -- BED THEM IN...

Then let us know if you can lock up all four wheels...

If you can't... you've still got some work to do.