53 Mercury power disc brake upgrade

[dean333]

I imagine there are separate kits to install front disc brakes and a power brake booster for a 53 Monterey. Who has the best kits? Thanks in advance.

Tim 678-773-5764

[flathead4rd]

I found that just converting to front disc brakes made a major improvement in braking. Try it first and if not satisfied you can always add on what you think will give you what you are looking for.

[dean333]

Flathead4rd… so just the disc upgrade was enough?

[dean333]

How about this kit, anyone use it?

[flathead4rd]

That's been my experience. I've also been using the original, under floor, master cylinder. I was instructed to remove it's residual valve. Been using this set up for many years with no problems. Disc in front drum in back.
















































master cylinder in my 50

[KULTULZ]

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KULTULZ ...

Entering uncharted territory ...

Originally Posted by flathead4rd

That's been my experience.

I've also been using the original, under floor, master cylinder. I was instructed to remove it's residual valve. Been using this set up for many years with no problems. Disc in front drum in back.

You are using an under-floor single reservoir MC operating both front disc and rear drum? With no RPV's?

Who instructed you to remove the RPV?

[flathead4rd]

The makers of the conversion kit I go from shoebox ford.

[emf]

Originally Posted by KULTULZ

KULTULZ ...

You are using an under-floor single reservoir MC operating both front disc and rear drum? With no RPV's?

Who instructed you to remove the RPV?

You would do well to listen to K... He helped me greatly when I went to front discs in my 54 Sunliner. Without his help, I would have screwed it up royally. On my 54, I used Wilwood discs, but not sure if they make one for a king pin front end...


Frank

[KULTULZ]

How is the conversion performing Frank?

[KULTULZ]

Originally Posted by flathead4rd

The makers of the conversion kit I go from shoebox ford.

THANX!

I was just curious ...

[emf]

Originally Posted by KULTULZ

How is the conversion performing Frank?

Couldn't be better. Only had one problem, Wilwood does not indicate in their instructions how to bleed their 4 piston caliper. I mistakenly bled all four chambers and had a very soft pedal. I called Leed, who made the MC and they informed me that I should only bleed the upper ports and leave the lower ports untouched. Worked like a charm. Again, thanks for your help...


Frank

[KULTULZ]

Originally Posted by dean333

How about this kit, anyone use it?

To me (IMO), not good.

Their kit uses GM D154 CALIPERS which are low drag and require a step-bore MC to operate properly and due to the variety of GM step-bore MC's, use a universal STYLE corvette DISC/DISC MC. The parts are also likely off-shore.

Maybe read thru this - https://www.wilwood.com/BrakeKits/Br...rey&option=All

Also, notice these kits (rotors) come through with FORD wheel mounting 5" x 4 1/2", whereas this period MERC was 5" X 5 1/2", so if you want all the wheel mounting patterns the same on the car, you will have to modify the front rotors stud pattern.

Are you considering manual or power brake?

REFERRING URL - https://www.fordbarn.com/forum/showt...=341467&page=3

Remember the 53 and 54 MERC use different spindles.

[wga]

https://www.classicperform.com/Store.../4852CBK45.htm

[KULTULZ]

Originally Posted by dean333

How about this kit, anyone use it?

To me (IMO), not good.

Their kit uses GM D154 CALIPERS which are low drag and require a step-bore MC to operate properly and due to the variety of GM step-bore MC's, use a universal STYLE corvette DISC/DISC MC. The parts are also likely off-shore.

Maybe read thru this - https://www.wilwood.com/BrakeKits/Br...rey&option=All

(If doesn't come thru correctly, SEARCH for 1953 MERC FRONT DISC KIT)

Also, notice these kits (rotors) come through with FORD wheel mounting 5" x 4 1/2", whereas this period MERC was 5" X 5 1/2", so if you want all the wheel mounting patterns the same on the car, you will have to modify the front rotors stud pattern.

Are you considering manual or power brake?

REFERRING URL - https://www.fordbarn.com/forum/showt...=341467&page=3

Remember the 53 and 54 MERC use different spindles.

EDIT - (The boy loves his edits)

Also don't fall for the EYE-CANDY CHEESE GRADER ROTORS.

They are a waste of good beer money.

[KULTULZ]

... ... umm ...

I have noticed something about this kit - https://www.wilwood.com/PDF/DataSheets/ds965.pdf -

...that has shocked the heck out of me ...

The INSTRUCTION SHEET reads can be used with original single reservoir MC.

The RPV located within the MC has to be removed (I can understand that).

I DON'T THINK SO!

The MC will not have enough fluid volume to properly operate the front disc and rear shoes. There will be no RESIDUAL PRESSURE VALVE for the rear shoes. I don't see anything about a PROPORTIONING VALVE in the sheet.

One poster even said to leave the rear shoes adjusted not so tightly as to allow the extra fluid volume in the calipers to return to the MC more easily ...

And this from WILWOOD, the most trusted name in braking conversions.

Am I just an OLD FART rattling or does anyone else see something wrong here?

[glennpm]

"Their kit uses GM D154 CALIPERS which are low drag and require a step-bore MC to operate properly"

The front disc brakes of this type do not use an RPV, i.e., low drag. However the drum brakes in the back do need a 10 PSI RPV. A rear brake proportioning valve may also be required.

Glenn

[KULTULZ]

Originally Posted by glennpm

"Their kit uses GM D154 CALIPERS which are low drag and require a step-bore MC to operate properly"

The front disc brakes of this type do not use an RPV, i.e., low drag. However the drum brakes in the back do need a 10 PSI RPV. A rear brake proportioning valve may also be required.

Glenn

I did not imply that. No disc brake setup uses a RESIDUAL PRESSURE VALVE, it (RPV) is only used in a DRUM BRAKE install.

GM (in this period) used a LOW-DRAG style of brake caliper. The caliper piston by design recedes further into the caliper (by design) so as to not allow the brake pads to contact the rotor surface during non-braking. It is a fuel and parts saver design.

Most any GM design based disc brake conversion kit will be using this caliper design (D-154 - METRIC)(CHI-CON SLOPPY COPY) and requires a STEP-BORE MC design to properly initiate piston movement with increased fluid volume.

Rather than supplying the correct GM MC to perform this (which would be difficult and expensive), the KIT MAKER will uses a CORVETTE style DISC/DISC MC to supply the needed extra volume.

When a brake job is performed in a shop and they use jobber calipers, the old caliper is turned in as a core and those cores go to a re-builder, where they are usually assembled as a low-drag caliper. Even when a caliper is replaced by either a shop or owner, most likely it will be low-drag and wonderment begins as to low performance. Both calipers housings are identical in appearance other than the STD will use a SAE tread bleeder screw whereas the metric will use a METRIC bleeding screw.

Some kit suppliers will not supply the needed correct design MC and the user will complain of low brake pedal and poor braking.

That it is why one must be very careful when buying a kit. Most of these kit sellers throw most anything into the box without any thought of safety.

[glennpm]

Originally Posted by KULTULZ

I did not imply that. No disc brake setup uses a RESIDUAL PRESSURE VALVE, it (RPV) is only used in a DRUM BRAKE install.

Disc brakes other than those that use a stepped bore, use a 2psi RPV.

[KULTULZ]

Originally Posted by glennpm

Disc brakes other than those that use a stepped bore, use a 2psi RPV.

The only time a #2 RPV is used (DISC) is if the MC piston bore in below the caliper piston bore. If a LOW DRAG CALIPER and/or STEP-BORE MC is used on an early application (MC under floor) it will also require a #2 RPV.

Do you post frequently on the H.A.M.B. site?

[glennpm]

Originally Posted by KULTULZ

The only time a #2 RPV is used (DISC) is if the MC piston bore in below the caliper piston bore. If a LOW DRAG CALIPER and/or STEP-BORE MC is used on an early application (MC under floor) it will also require a #2 RPV.

Do you post frequently on the H.A.M.B. site?

If you use a 2psi RPV check valve, you are keeping constant pressure on the rotors which is contrary to their "low drag" design function. For more common discs, there is a low pressure 2psi RPV and NOT only when the caliper is higher than the master cylinder. If you do use an 2 psi RPV, you still have the benefit of moving a lot of brake fluid from the go get, with less pedal travel. The stepped bore (SB) designs have a large primary bore to move a lot of fluid before 100psi is attained and the smaller bore takes over.

You can buy one of these SBs for around $40. Note that there are two GM designs, one has a primary bore around 1-1/2" and another 1-1/4". I have a 1-1/4" on my '32 with hydraulics. https://www.fordbarn.com/forum/showp...98&postcount=5

I post sometimes on the "Hokey Ass" site but sometimes you get incorrect info from posters with an attitude :-)