Markus wrote
"On going to 80mm front calipers. You will increase pad
pressure to the rotor, at the expense of more pedal travel.
When you go to a larger master cyl., the increase in
pressure will dissappear. There is a straight mechanical
relationship from the pedal movement to the caliper
pressure. When you have vacuum assist, the int. =
manifold vacuum will help to minimize pedal travel.
That's right, the vacuum assist isn't there to raise
the fluid pressure, but to lessen pedal travel. Of
course they are the same thing, but in reality there
should be some trade-off here, the device that sets
ultimate pad pressure is the size of the brake
booster's diaphram and you leg muscles."
Markus I agree with your comments on increasing
caliper/master cylinder sizes however I don't know
that I can agree with your comments regarding the
vacuum assist. It is my understanding that the vacuum
assist simply makes it easier for the driver to create
pressure on the fluid in the master cylinder. If this is true
then the only way the booster can minimuze pedal travel
is because of allowing for the use of different caliper/master
cylinders.
" Does the 80mm calipers use bigger pads, that would help."
153 pads are a larger version of the pads used on the GM. I
used them with the 80mm calipers but I believe they could
also be used with the stock ones.
"What about going to a Hydrolic Brake Booster like what's in a '83 diesel=
=
suburban. I have 2 suburbans, one with hydrolic and one with a vacuum
boost. =
The hydrolic booster can lock the wheels up at any speed. The vacuum boos=
t =
can't. Has anyone tried this. I've thought about swapping boosters to see=
=
what happens. As far as rear rotors, it seams like a lot of trouble for =
little gain. How has this conversion worked out for you all? Did it reall=
y =
help?"
I suspect the hydralic booster might help although size and
space may be an issue. After looking at the work Arch went
through to change his booster I figured I would leave that one
for the moment.
Regards
Gary Zingle
"On going to 80mm front calipers. You will increase pad
pressure to the rotor, at the expense of more pedal travel.
When you go to a larger master cyl., the increase in
pressure will dissappear. There is a straight mechanical
relationship from the pedal movement to the caliper
pressure. When you have vacuum assist, the int. =
manifold vacuum will help to minimize pedal travel.
That's right, the vacuum assist isn't there to raise
the fluid pressure, but to lessen pedal travel. Of
course they are the same thing, but in reality there
should be some trade-off here, the device that sets
ultimate pad pressure is the size of the brake
booster's diaphram and you leg muscles."
Markus I agree with your comments on increasing
caliper/master cylinder sizes however I don't know
that I can agree with your comments regarding the
vacuum assist. It is my understanding that the vacuum
assist simply makes it easier for the driver to create
pressure on the fluid in the master cylinder. If this is true
then the only way the booster can minimuze pedal travel
is because of allowing for the use of different caliper/master
cylinders.
" Does the 80mm calipers use bigger pads, that would help."
153 pads are a larger version of the pads used on the GM. I
used them with the 80mm calipers but I believe they could
also be used with the stock ones.
"What about going to a Hydrolic Brake Booster like what's in a '83 diesel=
=
suburban. I have 2 suburbans, one with hydrolic and one with a vacuum
boost. =
The hydrolic booster can lock the wheels up at any speed. The vacuum boos=
t =
can't. Has anyone tried this. I've thought about swapping boosters to see=
=
what happens. As far as rear rotors, it seams like a lot of trouble for =
little gain. How has this conversion worked out for you all? Did it reall=
y =
help?"
I suspect the hydralic booster might help although size and
space may be an issue. After looking at the work Arch went
through to change his booster I figured I would leave that one
for the moment.
Regards
Gary Zingle
