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--- John Fessenden fess <fess-vwtype3.org@fess.org> wrote: > however advice from this list was also that > the rear disc brake kits were useless, since > they were no longer balanced with the front brake > you would lock up the rears and get less overall > braking. I should note that discs are not inherently "more powerful" than drums. They have a number of advantages, including easier servicing, less likelyhood of fade, and not as much of a problem with water splashes. Sheer braking power, however, can be quite high for a good drum setup, until fade enters the picture. Brake balance is something of a tricky subject, and I don't want to write a whole treatise here on the subject. However, brake proportioning valves operate by reducing the amount of pressure available one pair of brakes (usually the rear) to get the right front/rear balance, so having rear brakes that are too powerful is actually *required* for a proportioning valve to work. There are a number of adjustable proportioning valves available for fairly reasonable prices. You actually want the front brakes to lock first in any actual situation. In a straight line, it doesn't matter all that much, but braking in a corner with the rears locked means you spin pretty much instantly. With the fronts locked you simply understeer straight on, which is easier to cope with in most situations. This is something of a problem for many cars, and esp. cars with relatively high centers of mass, as the weight transfers forward under braking, giving more traction to the front wheels and less to the rears, so the harder you brake, the less rear braking force you want. Some cars have employed dynamic proportioning valves to handle this, sometimes very simply. Many FIATs with solid rear axles had a lever arrangement with a link to the prop valve attached to the body above the axle. When the body rose away from the axle (as it will under braking), the prop valve reduced the rear brake power. The more the body rose, the less rear braking power there was. One could do a similar thing on a T3 by attaching the link to the rear spring plate. __________________________________ Do you Yahoo!? Take Yahoo! Mail with you! Get it on your mobile phone. http://mobile.yahoo.com/maildemo ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~