started a compilation of photos
that I've been taking while I
convert my '94 GT from the
pushrod 5.0L motor to a 4.6L
modular motor. I'll update this
as I get time...
are pictures of what it takes to
replace the existing vacuum
brake booster with a hydroboost
the master cylinder from the
vacuum brake booster. This will
require removing the steel brake
lines going to the master
cylinder. You will end up
replacing this master cylinder
with an updated one.
need to remove the stock vacuum
brake booster. To do this you
will need to go under the dash
and remove the rod that connects
the brake pedal to the booster.
There's a clip, a white plastic
washer, the brake pedal switch,
and a black plastic washer that
goes in the brake booster rod.
There are four bolts that will
need to be removed that hold the
booster to the firewall - these
are 1/2" nuts if I remember
correctly. They are a PITA to
loosen because of the tight area
to work in.
the booster from the firewall.
will need to cut 2 1/2" slits
about 1" from each of the top
bolt holes on the firewall that
connect the hydroboost to the
firewall. This is because the
hydroboost rod assembly that
connects to the brake pedal has
been located higher on that
bracket and it will hit the
firewall preventing you from
bolting the hydroboost up to the
firewall. Below is a picture of
what I had to do to make it fit.
You will also need to drill a
hole for the dowel that sticks
out of the hydroboost (as shown
in the picture below), or, you
could just remove the dowel all
together. I had already cut part
of the hole and decided not to
cut the rest so I simply
shortened the dowel so that it
would fit through the firewall,
but not the second plate that
sits 3/4" or so behind the
firewall (I believe that part is
part of the brake pedal
5. Now you
will need to modify the
hydroboost unit. Because the rod
in the hydroboost is at the
wrong angle compared to that of
the vacuum booster, you'll need
to cut off the end of the rod on
the hydroboost unit. Then, you
will need to cut off the end of
the rod on the vacuum booster
end. With the end from the
vacuum boost unit, you will need
to have this welded on to the
hydroboost unit making sure that
it's the same distance from
where the mounting studs are (I
measured about 5-5/16"). The new
welded assembly that I did looks
like the picture below. Another
option would be to replace the
entire pedal assembly with the
updated version and then you
wouldn't have to do this - but,
to me, that seemed like a lot
more work. Although, the
downside is that I'll have to
make this "upgrade" to a new
hydroboost unit if/when this one
the vacuum booster rod - you'll
notice it's at a different angle
than the hydroboost unit.
the newer hydroboost rod -
notice the angle is different.
side by side shot...
boot on mine was torn, so I
opted to use the boot from the
original vacuum booster.
This is the "upgraded"
hydroboost with the vacuum
booster rod end.
6. I cut
Finally, I bolted up the
hydroboost to the firewall. I
haven't found a bolt yet for the
lower left corner of the
hydroboost unit. When I get one
I'll post the one I used, but I
think anything that will secure
it would probably be sufficient.
haven't connected the master
Connecting the master cylinder
is next, however, I don't have
the correct one. The one I have
is at the wrong angle, so I'll
need to order a new one. I am
also looking into having custom
flexible brake lines made to
connect the master cylinder to
the distribution unit below it.
I'll update this when I get
Contact David at