Contour Enthusiasts Group Archives Forums Modifications Brakes Brake bias tools

With all the talk of brake bias the past few years, the spread of a lot of misinformation on forums and many people having little understanding of it, TCE has added an interactive calculator to its web page under the new heading of "Tools". The calculator is there for your use 24/7.

http://tceperformanceproducts.com/brake_bias_calculator.html

Linky no work

Fixed. Sorry browser cut/copy issues.

Thanks!

Looks great Todd! will be a useful tool for a lot of budding brake modifiers

I should pick on your calculation of pad effective radius, because it is too simple, but it is really irrelevant due to the natural variation of other factors, lik Cf, lol.

btw, speaking of Cf, you mention an average value of .38 for factory type pads; just an FYI, many factory pads these days are much closer to the .47 than you would expect. Many systems these days are sized a bit small, and the performance is made up with higher friction pads; which leads to a lot of the dust complaints people have with a lot of new cars.

I'll gladly change the Cf specs to spruce them up a bit more. You are right that they are spaced a bit more than should be.

You don't like ER= D/2 less PH/2 formula? I've often seen others show a lesser ER based on another formula. Generally a bit less than I'd get. I've often suspected it more relative to piston center and R than simply using the pad. But pad is pretty quick and easy to do...

Changed it to .42/.48 and .60

Nice, thanks!!

Todd, mostly just giving you a hard time about the ER, technically you need to find the centroid of the area of the pad, and the distance from there to the center of the rotor is the ER, but, it's tons more work, and requires more info (like the the entire pad shape) and the answer will virtually always be within a couple of mm of your calculation

I guess I'm just too sarcastic for my own good . . . but only because its not really funny to anyone else, lol.


btw, on the Cf, it's a tough call, because it's really a mixed bag these days still. Really, the right way to do it, is for a factory pad to be near .38 like you said, because it makes dust and noise and brake roughness much less of a problem from a warranty standpoint, but a lot of vehicles don't end up that way . . . I know of one passenger vehicle line (not a Ford) that when we had thier factory pad tested for Cf to compare to one of ours, it came out closer to .55, so take that for whatever you will, lol.

Ok, I'll make Street .40 in the notes.

Would the ER not be the 'centroid' of the piston relative to its placement on the rotor more than the pad? The center of clamping point woud be the piston not the pad. And I suppose a split bore the average of both?
*for the rest of you; we're probably making a bigger deal of this than you care to know

well, my understanding, is that it is the centroid of the area of the pad, rather than the radial center (which may or may not be the same, depending on the geometry of the pad) the piston location is "technically" irrelevant for the theortical calculation, because if you assume a stiff backing plate, all of the force from the piston is transferred through the pad and the same force is applied from the pad into the rotor, however, because the area of the pad is greater than the piston area, the pressure on the rotor face is less than from the piston to the back of the pad. Now, in the real world, pads can't easily handle offset forces, you do things w/ the pistons to fight taper wear, but the raw theoretical calc for ER is only based on pad centroid. Of course, in fairness, I don't even remember the proper method for determining the real centroid anymore, lol.

*and for those following along at home, we are definately straining at gnats here, Todd's calculator has a more than acceptable approximation. We are just being geeks, well at least I am, lol.