13 replies to this topic

[IMORAL]

What do Wilwood recommend?

 

I'm interested on this one day myself

[Bigfella237]

There are a heap of different considerations here, expected pedal travel multiplied by the pivot to pushrod ratio; the surface area of the master cylinder piston vs the total surface area of the caliper pistons in any given circuit; plus pad knockoff and caliper flex (how far the caliper pistons need to move before braking occurs) etc.

 

Generally speaking, the bigger the master cylinder piston diameter, the less pedal travel is required, but more pedal pressure. Or a larger fulcrum on the pivot ratio can also increase pushrod pressure, but in turn increases pedal travel. You will find that Torana brake pedals from unboosted vehicles had their pivot ratios setup differently from boosted systems, but finding one of these may be next to impossible?

 

With unboosted disc brakes you will likely want to keep the master cylinder diameter as small as you can without getting into excessive pedal travel as you're gonna need all the mechanical advantage you can get.

 

Have you ever been towed in a four wheel disc braked car? Once the booster vacuum runs out you can just about stand on the pedal before anything happens!

[dattoman]

Are you a chunky bloke or a lightweight ?

 

Standard Torana and usual recommened is 1"

But if you like the pedal lighter and more travel... try the 7/8

I prefer a firmer feel so I'd be using 15/16 or 1" or even 1 1/8" depending on the rest of the brakes

But I'm a chunkybum

[Bigfella237]

I thought I'd seen an online calculator somewhere on the Wilwood site to work out what suits what, but I don't seem to be able to find it now?

 

I did however run across a datasheet for Wilwood's "Dynamic Bleed System" which I hadn't heard of before, looks very interesting...

 

[Uncle Chop Chop]

And what is that supposed to do?

[IMORAL]

Add more unnecessary shit in your car by the look of it?

[gtrboyy]

Try 7/8 if you can..think softer more travel might give it better pedal feel

 

 

Had kingy m/cyl then xb falcon with twin piston fronts/single rears,as expected pedal was rock hard..I thought it was fine but everyone else thought car would either not stop or pushed too hard they'd go through screen but really all they'd end up with is sore leg.

 

I'm 125kg so wasnt a problem with concrete pedal except barefoot driving.

Edited by gtrboyy, 03 February 2017 - 01:25 PM.

[Bigfella237]

And what is that supposed to do?

 

From the Wilwood datasheet...

 

The Wilwood Dynamic Bleed System (WDBS) has been designed for maximum use brake applications where severe
rotor, pad and caliper temperatures are maintained for extended periods of time. The WDBS allows small amounts of
brake fluid to be circulated within a closed loop system each time the brake pedal is depressed. This helps to eliminate
localized fluid boiling and build-up of gases within the brake fluid, resulting in a firmer, more consistent pedal. The
WDBS consists of two (2) one-way flow valves and a special crossover return tube to replace the bleed screws (refer
to the diagrams below). Systems for the Prolites, Integras GT III, GT 6000, GT, GN III, and most Superlite calipers
are “in-stock” items and readily available. Applications include both single and dual master cylinder systems.

[madtoranajzedded]

How would you balance front and rear disc

So theres another master that goes beside it
for rears?

[Bigfella237]

Yep, that diagram was from a "Balance Bar Dual Master Cylinder Setup" but it would be no different with the separate circuits of a two-stage master cylinder.

 

From their documentation, they only mention this dynamic bleed system on the front brake circuit, I guess it makes sense that most of the braking is done by the front brakes so most of the heat would be generated by the front as well?

 

Although I see no reason you couldn't run it on both front and rear circuits, it just means you'd need to run extra "return" lines?

 

But yeah, what's next... if they're that worried about brake fluid temp, why not run a heatsink on the return to cool the fluid?

[Uncle Chop Chop]

Bigger brake ducts. Or ducks.