Black Magic drum brakes upgrade worth it?

[John Scoggins]

Length makes no difference. Say you had a hammer and 2 different punches...one being 6" long and one being 10 feet long. If you hold one end of each punch against a surface and smack the other end with a hammer...is the impact on the tip of the 10 foot punch going to be delayed compared to the 6" one? no. As long as the lines are full of fluid, length doesn't matter.

Fluid is compressible and furthermore fluid through lines does not act like a steel rod at all when subjected to compression.

 

[John Scoggins]

The hyd brake system is more similar to an electric circuit than a garden hose like I think you are using to base the delayed response of the rear due to longer lines. There is no air back filling the lines when you release the brake pedal. There is in your garden hose. That is the delay in pressure when you turn the spigot on. Brake fluid is completely filling the brake lines at all time so as soon as you apply pressure at one end it is the same throughout the entire system like when you turn on the light switch. There is no delay as the electrons fill the wire to the lightbulb. It is immediate.

Hydraulic and electronics can go had in hand (accumulator is a capacitor, diode is a check valve, resister is an orifice..... ) and I am not basing anything on a garden hose. Fluid is compressible and once compressed it then takes time for force to travel through the fluid to create pressure once that force is stopped. But in a brake system the lines are short and the volume is very small so it would be just about instant as far as pressure reaching the brakes at each wheel.

 

[mrblaine]

Fluid is compressible and furthermore fluid through lines does not act like a steel rod at all when subjected to compression.

Brake and most hydraulic fluid are not "compressible" and that very fact is why they are used in hydraulic systems. Compressible is in quotes because at the extreme levels of pressure there is a slight bit of compression that can occur but not at the pressure we see in automotive hydraulics.

 

[mrblaine]

Fluid is compressible and furthermore fluid through lines does not act like a steel rod at all when subjected to compression.

That is precisely the function and action.

 

[John Scoggins]

Brake and most hydraulic fluid are not "compressible" and that very fact is why they are used in hydraulic systems. Compressible is in quotes because at the extreme levels of pressure there is a slight bit of compression that can occur but not at the pressure we see in automotive hydraulics.

Agreed, the "average" compressibility is .5% volume per 1000psi so yup in a brake system is would make no difference, overthinking again. In the world of subsea hydraulics, like with my ROV's or even the Subsea hydraulic pumps it makes a very dig difference and has to be accounted for.

 

[John Scoggins]

That is precisely the function and action.

Where I use hydraulics it is not the same at all due to the fact of the volume and large fast pressure increases. Nothing of which is in a standard automotive brake system

 

[mrblaine]

Where I use hydraulics it is not the same at all due to the fact of the volume and large fast pressure increases. Nothing of which is in a standard automotive brake system

All works much better when kept in context.

 

[John Scoggins]

All works much better when kept in context.

LOL, yup

 

[Ephry73]

Unless you increase the size of the drum in the back as well as the cylinder and pads, the force the brakes will produce versus the front clamping force with bigger tires, should not lock up the rear. that said, upgrade your brakes all around if possible, specially if using bigger tires. Whenever I could, I always upgraded brakes when going a size up on tires.

New hoses, pads, shoes, rotors, etc... A good flush and bleed and should work better and keep you safe