Michael D. Porter wrote:
> Smaller cylinders will apply less braking force than larger cylinders,
> but if the force required to lock shoes against drum can be met by both
> cylinder sizes, the smaller will lock up earlier for a given pedal
> application. The master cylinder will pump a given volume of fluid; the
> smaller cylinder will extend further than the larger cylinder with the
> same amount of delivered fluid
Guys, can we think a little before we spread misinformation? This
isn't an opinion question, there is only one right answer.
Please remember that the back cylinders are connected. The
above logic depends on a false truth, that if the master moves
10cc to the rear wheels that each cylinder will get 5 so the small
will move farther and brake first. This is simply false.
Each cylinder will get as much fluid as will be admitted
AT A GIVEN PRESSURE. If one brake pad is much fatter, that
cylinder will get less fluid. If one slave cylinder is
a different diameter, it will get less fluid.
Towards this discussion, moving your foot to the floor will
move fluid to both cylinders simultaneously. One might
get more fluid and touch first, but UNTIL THE FREE SPACE
IN THE OTHER is consumed by fluid, you aren't exerting any
real pressure on the drum because the fluid pressure in
the system is very low because of free space on the other
side.
When all the dead space is consumed and ALL pads contact
the braking surfaces, then the pedal will start to
feel harder and real pressure is being exerted. Then it's
the leverage problem. This is a TR3 with one hydraulic
system for the whole car, so it's very simple.
--
.---------------------------------------Ottawa-Canada-GOSENSGO-----.
/ Trevor Boicey 1992 Celica GT 1975 MG Midget /
`----- tboicey@brit.ca -------...so close, but so far, gosensgo--'
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