[xj-s] brake balance

the use of semi metallic brakes on all 4 wheels is not a good idea in
that when the brakes are cold, such as in the mourning there is a
tendency for the car to not stop properly.
If you have any friends that have shops and the HUNTER brake tester you
can get a complete test of the the entire brake system as it is working
as a whole. It will test the front left, right and the rear left, right
balance to each other and to the whole system including a percentage of
which is doing how much including a test of the parking brakes and will
give the balance or efficiency of the front brakes as compared to the
rear brakes
I have found a company that does have the stainless steel bleeders in
some sizes and the rest come with a salt spray corrosive protective
covering on them
as for the stainless steel brake hose I found out the threaded ends are
cadmium coated for rust prevention. but otherwise the hose that I got
was perfect
As for the wearing of the rotors I have seen from personal repairs to
these systems that the wear factor is about 1,000 miles to about one
thousandth of an inch, so in about 80,000 you will need to replace the
rotors

walt

the use of semi metallic brakes on all 4 wheels is not a good idea in
that when the brakes are cold, such as in the mourning there is a
tendency for the car to not stop properly.

Gotta argue that one with ya, Walter. I have been doing the metallics on all
four for a few years and have not found this to be true. Some metallics ARE
harder than others and do take some time to warm up, but I have found this
to be more of a problem with the front brakes needing to be warmed up.

If you have any friends that have shops and the HUNTER brake tester you
can get a complete test of the the entire brake system as it is working
as a whole. It will test the front left, right and the rear left, right
balance to each other and to the whole system including a percentage of
which is doing how much including a test of the parking brakes and will
give the balance or efficiency of the front brakes as compared to the
rear brakes

Will this unit work with the ABS systems? Can you give us a little more
info? I have never heard of this…how do it work?

I have found a company that does have the stainless steel bleeders in
some sizes and the rest come with a salt spray corrosive protective
covering on them
as for the stainless steel brake hose I found out the threaded ends are
cadmium coated for rust prevention. but otherwise the hose that I got
was perfect
As for the wearing of the rotors I have seen from personal repairs to
these systems that the wear factor is about 1,000 miles to about one
thousandth of an inch, so in about 80,000 you will need to replace the
rotors

I have found that this wear factor changes with the use of a particularly
harsh metallic pad set. But I stll would rather have good brakes and replace
rotors more often.
Cheers,
JebFrom: “walter acker IV”

Lisa & Jeb Boyd wrote:

From: “walter acker IV”

the use of semi metallic brakes on all 4 wheels is not a good idea in
that when the brakes are cold, such as in the mourning there is a
tendency for the car to not stop properly.

Gotta argue that one with ya, Walter. I have been doing the metallics on all
four for a few years and have not found this to be true. Some metallics ARE
harder than others and do take some time to warm up, but I have found this
to be more of a problem with the front brakes needing to be warmed up.

Walter, I wouldn’t say that the car has “a tendency for the car to not
stop properly,” because it gives the wrong connotation. What I would say
is that the stopping distance can be a bit longer when the pads are
cold. My experience is that this affect is much more pronounced on a
non-power-brake car. Power brakes tend to apply enough force at the pad
that they heat up pretty quickly and the longer stopping distance is
rarely even noticeable after one stop. I do still remember strongly the
first time I tried to stop my '75 base-model Rabbit after putting a set
of MetalMasters on it. Whoo-weee!!

As a historical aside, Chevrolet (& GM?) tried a metallic pad option in
the early '60s termed Cerametallic, though they were considered part of
the racey-car option set, like “heater delete.” They didn’t sell them
for very long because of the lengthened cold stopping distances and the
fact that street car owners liked to select the race-car intended stuff,
too.

(snip)

As for the wearing of the rotors I have seen from personal repairs to
these systems that the wear factor is about 1,000 miles to about one
thousandth of an inch, so in about 80,000 you will need to replace the
rotors

Having to replace rotor every 80,000 miles doesn’t sound like excessive
wear to me! When I ran the parts department for a large BMW specialist
here for a 10-year period, we used Repco MetalMasters exclusively and
never observed excessive rotor wear. I have used them on my own cars for
over 20 years and have not seen excessive rotor wear rates. That being
said, there probably are metallic pad formulations that are harder on
the rotors, but I wouldn’t tar the entire category with that brush based
on my experiences.

What I like are the MetalMasters (no longer sold as Repco brand BTW) is
the decreased dust throw-off, their complete lack of heat-induced fade,
and the fact that I feel they decrease stopping distances by something
like 5-10% (subjective number).

Damn, I hate agreeing with Jeb all the time!

Best regards,

Gregory Wells
Coventry West, Inc.
New, Rebuilt, & Used Jaguar Parts


800-331-2193 x103

From: “walter acker IV”

the use of semi metallic brakes on all 4 wheels is not a good idea
in that when the brakes are cold, such as in the mourning there
is a tendency for the car to not stop properly.

Gotta argue that one with ya, Walter. I have been doing the
metallics on all four for a few years and have not found this to be
true. Some metallics ARE harder than others and do take some time to
warm up, but I have found this to be more of a problem with the
front brakes needing to be warmed up.

Walter, I wouldn’t say that the car has “a tendency for the car to not
stop properly,” because it gives the wrong connotation. What I would
say is that the stopping distance can be a bit longer when the pads
are cold.

Why? Seems to me the stopping distances when cold are limited by the
tires, not the brakes. If the tires are cold and need warming to
avoid sliding, fine, but if the brakes aren’t stopping fast enough,
push a little harder on the damn pedal!

My experience is that this affect is much more pronounced on
a non-power-brake car. Power brakes tend to apply enough force at the
pad that they heat up pretty quickly and the longer stopping distance
is rarely even noticeable after one stop. I do still remember strongly
the first time I tried to stop my '75 base-model Rabbit after putting
a set of MetalMasters on it. Whoo-weee!!

OK, I’m confused. Just what difference will power brakes make on how
hot the pads get? And you actually found a Rabbit without power
brakes?

As a historical aside, Chevrolet (& GM?) tried a metallic pad option
in the early '60s termed Cerametallic, though they were considered
part of the racey-car option set, like “heater delete.” They didn’t
sell them for very long because of the lengthened cold stopping
distances and the fact that street car owners liked to select the
race-car intended stuff, too.

The XJ-S has been fitted from the factory with semi-metallics since
VIN 109447. Have there been a lot of problems with inability to stop
when cold? The only thing I can figure is you guys are talking about
something else. I’ve been using semi-metallics since the 70’s in
everything from British sports cars to Hondas and I have never had
a problem stopping.

– Kirbert | Palm’s Postulate:
| If anything is to be accomplished,
| some rules must be broken.
| – Kirby Palm, 1979From: Gregory Wells sales@coventrywest.com

Kirbert wrote:

(snip)

Walter, I wouldn’t say that the car has “a tendency for the car to not
stop properly,” because it gives the wrong connotation. What I would
say is that the stopping distance can be a bit longer when the pads
are cold.

Why? Seems to me the stopping distances when cold are limited by the
tires, not the brakes. If the tires are cold and need warming to
avoid sliding, fine, but if the brakes aren’t stopping fast enough,
push a little harder on the damn pedal!

With metallics, there is a huge difference in the coefficient of
friction of the pad material cold vs hot. Cold, there isn’t much
friction at all. Hot, they grab very well.

My experience is that this affect is much more pronounced on
a non-power-brake car. Power brakes tend to apply enough force at the
pad that they heat up pretty quickly and the longer stopping distance
is rarely even noticeable after one stop. I do still remember strongly
the first time I tried to stop my '75 base-model Rabbit after putting
a set of MetalMasters on it. Whoo-weee!!

OK, I’m confused. Just what difference will power brakes make on how
hot the pads get? And you actually found a Rabbit without power
brakes?

It is my supposition that power brake systems can apply a greater force
to the pad and thus cause them to heat up faster, i.e. during the first
brake application. This is just my WAG. But full metallic pads on a
non-power brake car give a first stop (i.e. with cold pads) quite a bit
longer than when they’re warm. Been there, done that, have the dirty
diaper to prove it; it is not supposition and I invite you to experience
it for yourself if skeptical :-). I don’t notice the affect hardly at
all on a car with power brakes. And 1975 base-model VW Rabbits do not
have power brakes (I didn’t buy it, I married its owner).

As a historical aside, Chevrolet (& GM?) tried a metallic pad option
in the early '60s termed Cerametallic, though they were considered
part of the racey-car option set, like “heater delete.” They didn’t
sell them for very long because of the lengthened cold stopping
distances and the fact that street car owners liked to select the
race-car intended stuff, too.

The XJ-S has been fitted from the factory with semi-metallics since
VIN 109447. Have there been a lot of problems with inability to stop
when cold? The only thing I can figure is you guys are talking about
something else. I’ve been using semi-metallics since the 70’s in
everything from British sports cars to Hondas and I have never had
a problem stopping.

One of the reasons for semi-mets is that they are half-organic and they
do not display the same cold characteristics. Semi-mets tend to give the
benefits of both types of friction materials without the drawbacks of
either.

My points about metallics are in reference to full metallic pads only. I
can’t recall ever using a set of semi-mets on one of my own cars.

Best regards,

Gregory Wells
Coventry West, Inc.
New, Rebuilt, & Used Jaguar Parts


800-331-2193 x103

Why? Seems to me the stopping distances when cold are limited by the
tires, not the brakes. If the tires are cold and need warming to
avoid sliding, fine, but if the brakes aren’t stopping fast enough,
push a little harder on the damn pedal!

I ran carbonmetallic street/track pads on my Firebird, and they DEFINITELY
stopped worse cold. However, that’s kind of an extreme example, and I’ve
never had any problems with street pads.

Cheers,
Bry