RBBailey - What you describe as your schedule is very reminiscent of why it took me years to get my D1 300TDI R380 project done.
DI Brakes Just Not Good Enough
- Thread starter RBBailey
- Start date
I've ordered SS lines, but since the brake rotors and pads look like a lot of life left in them, I'm going to try new lines before anything else.
But here is another question:
When I bought this truck, the ABS light was OFF -- that is, it was doing exactly as it should. It would be on at start, then turn off once driving. I noticed that it seemed a bit more likely to go OFF if I drove straight for the first 50 feet or so. But over the last month or two, it has started staying on more than likely. And now it stays on almost all the time. When it is ON, the ABS indeed is not working. There is a slightly less aggressive feel to the braking, and the wheels can be locked up. Any thoughts on this?
But here is another question:
When I bought this truck, the ABS light was OFF -- that is, it was doing exactly as it should. It would be on at start, then turn off once driving. I noticed that it seemed a bit more likely to go OFF if I drove straight for the first 50 feet or so. But over the last month or two, it has started staying on more than likely. And now it stays on almost all the time. When it is ON, the ABS indeed is not working. There is a slightly less aggressive feel to the braking, and the wheels can be locked up. Any thoughts on this?
If the light is ON, check the codes. Unless you get 2-0, it should be fixable.
Even with stock-sized tires, new, the Discovery never had great brakes, no matter what kind of pads you used.
Improving brakes is relatively simple to understand. There aren't too many factors at play, but there's more than just removing heat energy.
The rotor is a lever. That means the bigger, the better... To a point. You don't want a six foot rotor on a Caterham R500 Superlight, and you have to watch the ratio between the front and rear. Also, the bigger it is, the more surface area exists to radiate heat, and the more thermal capacity it has. This is why rotors are still made of cast iron, even though it's heavy and prone to rust.
Changing to slotted rotors improves pad wear patterns under adverse conditions and in general if you're using floating calipers (we are), at the expense of service life.
Drilled rotor utility is questionable on the street, but they do indeed vent expelled gasses as described.
The master cylinder to slave cylinder ratio determines how much pressure is applied to the end of that lever that is the rotor.
Fitting more pistons allows stretching that ratio further and provides more even pressure across the pad, as well as further conduction.
Moving from floating to fixed calipers improves contact and stability, as well as conduction, and also lets you take that ratio even further.
Hardening up the lines ensures that your foot application to the pedal isn't wasted at all.
The brake pedal is also the end of a lever, and that can be adjusted to change the required force application.
Pad choice determines the level of friction versus service life, as well as ratio of material wear in regards the pads and rotor.
Pads also change when the brakes begin to function efficiently. Some handle high heat, but need to warm up before they start to work, and some work immediately (factory stuff), but don't perform well at high temperatures.
This is literally elementary school geometry and hydraulic theory. Don't let yourselves be caught up so much in part numbers that you miss the forest for the trees. If you know the dimensions of everything, you immediately know whether or not it will be an improvement, as well as roughly how it will feel at the pedal.
It's very easy to become distracted by part numbers, convention, experiences, and common practice. It makes all this seem more complicated than it is.
Cheers,
Kennith
The rotor is a lever. That means the bigger, the better... To a point. You don't want a six foot rotor on a Caterham R500 Superlight, and you have to watch the ratio between the front and rear. Also, the bigger it is, the more surface area exists to radiate heat, and the more thermal capacity it has. This is why rotors are still made of cast iron, even though it's heavy and prone to rust.
Changing to slotted rotors improves pad wear patterns under adverse conditions and in general if you're using floating calipers (we are), at the expense of service life.
Drilled rotor utility is questionable on the street, but they do indeed vent expelled gasses as described.
The master cylinder to slave cylinder ratio determines how much pressure is applied to the end of that lever that is the rotor.
Fitting more pistons allows stretching that ratio further and provides more even pressure across the pad, as well as further conduction.
Moving from floating to fixed calipers improves contact and stability, as well as conduction, and also lets you take that ratio even further.
Hardening up the lines ensures that your foot application to the pedal isn't wasted at all.
The brake pedal is also the end of a lever, and that can be adjusted to change the required force application.
Pad choice determines the level of friction versus service life, as well as ratio of material wear in regards the pads and rotor.
Pads also change when the brakes begin to function efficiently. Some handle high heat, but need to warm up before they start to work, and some work immediately (factory stuff), but don't perform well at high temperatures.
This is literally elementary school geometry and hydraulic theory. Don't let yourselves be caught up so much in part numbers that you miss the forest for the trees. If you know the dimensions of everything, you immediately know whether or not it will be an improvement, as well as roughly how it will feel at the pedal.
It's very easy to become distracted by part numbers, convention, experiences, and common practice. It makes all this seem more complicated than it is.
Cheers,
Kennith
I don't think anyone has done it (swapping late RRC brakes into a D1) - and many people done exactly the opposite.
But, out of my three late Classics and two early NAS D1s, Classics' brakes are by far and large superior.
Both are WABCO units, but there are differences.
That's kind of my thought as well, after looking at the pad thickness and thinking through the fact that they don't look like they have been ground down at all, after almost 2 years.... logically, that means they aren't providing friction. The new master had to be done because it was blown. I put Speedbleeder valves in, and have 100% new fluid in the lines. But the hoses are original, so I'm replacing those with stainless. Pads are next. (After I get new lugs.)
Almost true.
But one can use a working pump from a P38A, which are nowhere as rare.
Totally agree!! My RRC brakes are hands down better than the D1. And I only use genuine LR pads, etc on the D1. As well as the RRC for that matter.
The D1 brakes work yet the pedal feel is very different. I just deal with it when driving it.
It is not a straight swap, it needs some work.
When I run out of semi-working RRC pumps, I'll get on it.
Easier solution is to pull the tube that houses the electric drive motor, which splits from the main unit with 3 hex bolts. The P38’s is pretty much identical and bolts right in, IIRC on those trucks they use an adapter loom that changes from the RRC style socket to something else.
Tons of new, probably rebuilt motors are floating around for about $240.
ABS REPAIR KITS – Mototeknika
mototeknika.com
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