Brake Systems Part 1-A : Intro
Your brakes suck. You can go to a dealership first thing tomorrow morning and lay down $60,000 for a brand new BMW 5 Series. And guess what? You�re brakes will still suck. Mr. Glenn Reynolds, with your brand new RX-8, your brakes suck.
The vast majority of the stock brake systems released by the automotive manufacturers are just about worthy of criminal charges. Most are barely better than a �Run-away Rollercoaster of Death� (RRD). There are no real standards set by the government for stopping distances. As long as when you put your foot on the pedal and the car stops eventually, the feds are happy. Nice to know that they care so much, huh?
The only things that keep the manufacturers competitive with each other are the market place and the court system. If you read up on your new cars out there, you will find a 60-0 braking test. This is where they measure the distance a vehicle takes to come to a complete stop from 60mph. Almost every car, in my mind, fails this test, as they just take too much space to stop.
People actually read and absorb this information. And not just wrench turning, knuckle-heads like me. Soccer moms and refrigerator salesmen read this stuff when they are looking to buy a car. You might not. But you should.
While I don�t give a second thought to losing a reader because they disagree with me, or they take offense to something I say, I would hate to lose one, even temporarily, to something as avoidable as an auto accident. Which is why I have decided to share my knowledge of making cars safer (and faster, but we�ll get into that later this fall) with you.
I am a notorious �late-braker�. That means that I have a tendency to wait until the very last second to apply pressure to the brake pedal to slow my vehicle down. I not only pull away from other vehicles as I accelerate, I also see them fall back as we enter a corner together. I have utter and complete trust in myself and my vehicle�s brake system. I�d better, I put it together myself. I do this to every vehicle I own. Why? Because I like to brake late. That and the wife tailgates like a madwoman.
I have beaten lesser drivers in faster vehicles by entering the corner faster, hitting the apex of the turn at a faster rate of speed, which gave me the ability to exit the corner at a higher speed. All this helps me fit my exit out of the turn into my cars �powerband� and continue on. Two-Bit Charlie back there thinks I�m crazy, but he is still only able to see my taillights. He may have dumped a few grand into his engine. But he forgot that to be able to kiss the pretty girl at the end of the track, he is going to have to stop first. And unless I screw up or have a mech-fail, taillights is all he is going to see.
I own a 1997 Ford F150. With an aftermarket canopy and bedkit, it weighs just shy of 5,000lbs with a full tank of gas. I have made, what I consider, the necessary improvements to its braking system, and it now stops, from 70mph, in the length of a semi, with a full length trailer plus 5ft. And with what I will describe in these posts, you can get just about any vehicle to do the same or better.
So here we go.
Part 1-B : Brake Systems (hit the more button)
There are two major types of braking systems in use today:
The drum brake,
And the disc brake.
I�m just going to start off here and let you know that drum brakes are horrible. Unreliable and pathetic in their use of mechanical hydraulics, they should be outlawed on all newly manufactured vehicles. They are not even worthy of trust in use as a parking brake.
Drum systems use a wheel cylinder that contains opposing dual pistons to push two brake shoes, with friction surfaces on their outer edge, against the inside walls of steel cup (or drum, hence the name) which is connected to your wheel. When pressure is applied to the brake pedal, the wheel cylinder expands and pushes the pistons out. Which spreads the brake shoes and pushes them against the drum? Halting the motion of said drum, stopping the wheel and tire.
Drum brakes require almost constant maintenance to keep them working properly. Unless you feel like tuning up your brake system on a weekly basis, this style of brake will cause your car 1. To take forever to stop, and 2. Will cause your car to swerve, sometimes uncontrollably to a crooked stop. You have a greater chance of losing control and, more than likely, you will end up sliding out of your lane of travel. And remember, if your car careens out of your lane, you run the risk of colliding with oncoming traffic or going off the road completely.
Disc systems consist of a caliper that contains a piston and opposing clamp. When pressure is applied, the piston pushes out and draws the clamp in, causing them to work together to clamp down on the disk which is connected to your wheel, stopping the wheel.
Disc brakes also require maintenance to work at maximum efficiency, but nowhere near as much as drum systems. They also use the power of mechanical hydraulics more efficiently.
Most vehicles today are equipped with front disks and rear drums. Halfway to decent. We will do what we can to make you safe. But your standard equipment is lacking and there is only so much we can do to improve it. But have faith; we will get you taken care of.
If you own a sports car or even a �sporty� car (yes, there is a difference) you probably were given 4 wheel disc brakes. Congratulations, you have the least crappy brake system on the road. Follow the instructions here and you too will see the promised land of high safety.
If you have an older car with 4 wheel-drum brakes, whip out your wallet. There are conversions for most of the popular muscle cars for 4 wheel discs, but they aren�t cheap. But you probably already knew this if you�re serious about older cars.
This week I am going to cover brake fluids, brake fluid lines, and their maintenance.
Part 1-C : Lines, fluids and their maintenance.
When you push on your break pedal you are using the hydraulic pressure from your brake master cylinder (MC) to stop your vehicle. The pressures and temperatures involved here would make you cry if you knew just how vulnerable you are to failure in this regard. But that is what I am here to help you through. So go get the Kleenex and we�ll get our toes wet together.
When the fluid leaves the MC it travels through steel lines to within usually 12-18 inches of your wheel. Because of the turning and/or up and down motion needed of your wheel, it switches to a flexible hose to continue the flow of fluid to your respective caliper or wheel cylinder. This hose is, unfortunately, usually made of rubber. This rubber, over time will deteriorate, leading to leaks and loss of pressure. It is the weak point of your brake hydraulic system.
Which is why you need to junk them and get a set of these?
Braided steel brake lines.
Why? When the pressure is sent through the system to you brakes, the wheel cylinder or caliper is going to push the fluid back at the same rate, if not more. Remember Newton? The pistons don�t want the fluid, the MC doesn�t want the fluid back and the steel portion of your lines won�t expand. But your rubber hoses will. Think of how many times a day you press on that pedal. Each time you do you are expanding that little hose. Over time the hose won�t even put up a fight when asked to expand. This leads to a squishy pedal feel and then to no pedal feel. Once this happens, you are one emergency stop away from a ruptured line.
But the steel braided lines expand so little because, well, they�re wrapped in steel. This also gives them a much longer usable life. They aren�t very expensive and are made for almost all vehicles. Here is a Google search for �Steel Brake Lines�. Take a look around. Or head off to your local auto parts store.
You should get your brake system inspected at a respectable shop a minimum of every 20,000 miles. Make sure they check all parts including these lines. There is no repair available for worn lines. Replacement only.
The government standard for brake fluid is called DOT 5. This designates the minimum level of consistency in the fluid in order to make the brake system function. You can buy this stuff off the shelf at just about any hardware or auto parts store. But don�t. It is junk.
Braking occurs because of friction. Friction causes heat. Heat sucks. If you stay up and watch a night race, say the 24 Hours of Le Mans, you will see something spectacular. Their brake discs are glowing. Red, orange and yellow circles can be seen inside of their wheels. This rise in temperature is transferred throughout the whole braking system. Including the fluid. I have seen DOT 5 boil in a reservoir. This is scary. Remember the rubber brake lines?
Also, standard brake fluids are silicone based. This gives them a non-hydroscopic problem. Non-hydroscopic means that it will not mix well with water and will give you a fluid/water/fluid situation. Bad, bad, bad. The competition fluids are of a poly-glycol base. They will mix OK with water, but the presence of H2O will lower their boiling point drastically.
If you have ever seen standard brake fluid you will see that it has the consistency of soda pop. What you want to do is switch out this fluid for something with more thickness. Something like a good maple syrup would be nice. Molasses would be better. The more pounds per square inch (PSI) you can get to you brake pistons with the least effort the better.
There are many performance grades of fluid. From a DOT5.1 to a racing grade DOT 3. These different grades have different consistencies and boiling points. I use 5.1 in the wife�s car, but I won�t endorse the grade I use in my truck. Can�t give away all my secrets here. Check with a mechanic or two before going above 5.1. Here is a link to a Google search for �Brake Fluid Racing�. Take a look around.
I wouldn�t suggest you switch to a heavier fluid until you upgrade your brake lines, which is why I listed them first. Also, NEVER COMBINE BRAKE FLUIDS! That is a big no-no. Beep-boop-bop-boop-beep, Hello trouble?
You can get both of these upgrades done at a reputable shop. It is best to do them both at the same time. Save up for each step if you have to. I cannot insist enough on doing this.
Please, always refer to a qualified shop before trying out any suggestions stated here. Trying to do this yourself could lead to serious problems. Thanks and be careful out there.