Front Suspension and Disk Brake Upgrade

[OX1]

Had a different idea for the fulcrum
setup last night. Drew up a quick sketch.
This would sort of, put both pedal and
booster rods in double shear, and should
strengthen the entire setup.

Hope to get this mostly knocked out
this weekend...........

[DKheld]

You better hurry - all that snow you guys just got may melt - about May -

The combo valve works terrific on my particular set up - maybe you could put yours down on the frame like I did but hide it with a heat shield / cover of some type?

But heck - with that jumbo jet booster in there I don't think you would see anything below it anyway.

Excellent work - looking really good.

Eric

[OX1]

HA!!, already gone, thank you Mr. (Miss??) El-nino, nina, whatever..........

I'd like to use the old cast iron looking
comb valve, for looks. But as you mentioned,
who is ever going to see it, as I probably will
put it under the booster.

Thanks for the kudos on the job, got the fulcrum
setup fab'd and welded this weekend. Hard to
believe first car shows are a little over a month away.
Have to start pounding out the suspension and disk
brake part of this soon......

Found these factory like Split Flanged Sleeve
Bearing @ McMaster Carr. Luckily for me, they
are about 20 minutes away from my house. Real
nice I can order something @ 5 AM, and go pick
it up by lunch. Not too much they don't have and
all real good quality.

https://www.mcmaster.com/#1281n16/=16c311c

all fab'd up




Needed one of these

https://www.mcmaster.com/#92415A928

and two of these

https://www.mcmaster.com/#92415A917

Cut to length and drilled out to 1/2 inch and 3/8
inch respectively. Unfortunately, could not find
the ID/OD combo I wanted, so had to drill.

You better hurry - all that snow you guys just got may melt - about May -

The combo valve works terrific on my particular set up - maybe you could put yours down on the frame like I did but hide it with a heat shield / cover of some type?

But heck - with that jumbo jet booster in there I don't think you would see anything below it anyway.

Excellent work - looking really good.

Eric

[DKheld]

Glad to hear the bad weather didn't hang around too long. We had a record high yesterday of 72. Car shows and cruise-in's are just around the corner.

No problem on the kudos - well deserved.
I'm just jealous - wish the bracket I made to move the booster out for the A/C install turned out as well.

Pic of my bracket when I was installing it. Just a small spacer actually between the firewall and original booster that I kept. Was just needed to move the booster out to clear the original type A/C evap box I was installing on the firewall ....so a little different build than yours. Couple of pieces of angle iron welded and a grinder to whip it into shape.





I was trying to replicate the original bracket/spacer available from dealer. Even came with a longer pedal "rod".



Eric

[OX1]

Couple questions just for kicks.

Do you know what the reduction ratio was for that fulcrum setup?

What was your MC from and did it require modification
to fit with original booster?

Also, I forget 352 or 430?

Glad to hear the bad weather didn't hang around too long. We had a record high yesterday of 72. Car shows and cruise-in's are just around the corner.

No problem on the kudos - well deserved.
I'm just jealous - wish the bracket I made to move the booster out for the A/C install turned out as well.


Eric

[DKheld]

Mine is 90% original as far as the booster goes. Well - 90% original Ford. I had my original booster rebuilt when I rebuilt the drum system but then bought a used unit to send off for modification rather than modify my original one when I decided to convert to disc's.

Kept the original booster because at the time I was thinking I might someday win the lottery and want to restore the car to like new original condition. Oh brother was I ever dreaming.

Mods are the little spacer between the original bracket and booster (pretty hard to see in the pic). Basically it just moved the original system up and out about 1 3/4 inches which is why the kit came with a new longer pedal rod. The original booster face was replaced with one from a '62ish Lincoln. Apparently Ford/Linc/Merc used that Bendix booster on later cars but changed the face to accept the 2 bolt style master cyl.

No idea on the fulcrum ratio but that is the original bracket riveted to the original (but rebuilt) booster. Sent it to Power Brake Booster Exchange in Oregon (aka Booster Dewy). He must know what he's doing and use quality parts - been 10-12 years and it still works fine. He also did the change on the front only because no one else had a clue what he used to make the switch. Not much info on the web back then either.



Master Cyl is a Mustang or possibly Lincoln Mark series unit. Can't put my hands on the receipt at the moment.
Looks like some numbers on the end are 1506 and 60101?

Yea - 352 - My Dad bought it brand spankin' new (but probably a leftover model late in '60 or maybe early '61). In this pic it has a 430 air cleaner (different snorkle). I had drilled some holes for a PCV system in the air cleaner and once again didn't want to modify the original one.





edit:
Ah ha - found a pic of my home-made shade-tree bracket. Bought a used pedal rod from Carl Heller and extended it. My bracket didn't move the system up - only out so it was easier to modify the pedal rod.

[simplyconnected]

...After measuring for hours, I came up with a Fulcrum bracket that will be 4.25/2.25 or 1.88 ratio, making my pedal ratio 6.23/1.88 or 3.31. Stock with the
bracket I had, was 2.88.

I can tell you that the ratio we came up with was 1.14:1 for our fulcrum. We used the stock brake pedal hole. Again, the booster is a dual diaphragm 8" that fits either the 430 or 352, A/c or not. - Dave

[OX1]

The original booster face was replaced with one from a '62ish Lincoln. Apparently Ford/Linc/Merc used that Bendix booster on later cars but changed the face to accept the 2 bolt style master cyl.

Master Cyl is a Mustang or possibly Lincoln Mark series unit. Can't put my hands on the receipt at the moment.
Looks like some numbers on the end are 1506 and 60101?

Yea - 352 - My Dad bought it brand spankin' new (but probably a leftover model late in '60 or maybe early '61).

Ah ha - found a pic of my home-made shade-tree bracket. Bought a used pedal rod from Carl Heller and extended it. My bracket didn't move the system up - only out so it was easier to modify the pedal rod.

OK, so it looks like the same MC ford used in most everything in the 60/70's and even early 80's.

My dad bought my mom a 60 in 60 too. He still has it, but it is a total basket case.
I thought of restoring, but he is 87 now and may not be driving too long.
This is why I have to get disk brakes done before spring, so he can drive it here and there.
I don't trust him with the stock brakes as bad as they were.

So it is the brake pedal rod that moves everything up a decent amount, vs the fulcrum setup.
My brake booster rod does angle up somewhat, near the top of the factory hole in firewall.

I can tell you that the ratio we came up with was 1.14:1 for our fulcrum. We used the stock brake pedal hole. Again, the booster is a dual diaphragm 8" that fits either the 430 or 352, A/c or not. - Dave

So the overall is 5.54. That's man brake ratio territory, but I guess it gives you enough leverage,
if you don't mind the large pedal travel. I guess if master and calipers are also smaller, probably
works well enough. Tough with brakes being subjective. One guys great brakes are anothers
guys horrible brakes.

[simplyconnected]

...So the overall is 5.54. That's man brake ratio territory, but I guess it gives you enough leverage,
if you don't mind the large pedal travel. I guess if master and calipers are also smaller, probably works well enough. Tough with brakes being subjective. One guys great brakes are anothers guys horrible brakes...

There are a few things we need to talk about. First, my brakes are very easy for any lady to operate. We use a one-inch master cylinder bore. Our S-10 calipers (and Granada) have 2-1/2" pistons. They work very similar to my wife's Ford Escape and they will lock up the wheels.

Next, I use the term "fulcrum" very loosely. A fulcrum point is a center pivot, much like a kid's see-saw where both ends pivot about the middle.

Our center link is fixed to the firewall bracket and it pivots at the bottom bolt, not the center pin. All motion from that bottom bolt is measured as an arc, where the middle pin moves about half the distance as the top pin. You can see this if you make a paper model and try it. Another illustration is to use a 'school compass.' Start on a vertical with the pivot point always at the bottom. Move the pencil end drawing the arc at the top pin, then draw a line at the end of that arc back to the pivot. Now draw the center pin arc to that same line.

Even though the angle of theta still remains the same, the length of your center link makes a huge difference in how 'flat' the arcs are. The arc travel or length ratio moves exponentially, (like F-stops on a camera). At 'vertical' the travel is nearly the same but as the travel becomes longer, the ratio changes, where a small center pin distance equals a huge top pin distance as the arc lengthens.

So how do you overcome this? Two ways:
Either start with the center link 'cocked back' so the center of motion is vertical to the bottom pin OR make your center link as long as possible. In other words, drop the bottom pin so 1/2" of top pin travel makes a flat arc.

All this manipulation of the center link angle/length will vary the feel of your brake pedal because the ratios automatically change with travel distance. Not so with a fulcrum.

If I lost you, make a long (10") paper center link on top of a standard sheet of paper with lines. Kick the bottom pivot out so it is vertical with the RH edge of the paper. Now, lean the top back towards the LH edge of the loose-leaf and draw a line to the pivot point. As the top pin moves forward (right) each 1/2", draw a line down to the pivot, repeat until link is vertical. Now remove the link and measure the center pin travel at each line you drew. This is your brake pedal rod. The distance/ratio (from the LH edge of your paper) becomes longer at each 1/2" until vertical. That also means, the same foot pressure becomes greater at the top pin. - Dave

[DKheld]

If I were converting today I would definitely go with the Scarebird brackets, rotors and calipers Dave points folks to on the forum - basically stay away from the Granada stuff. It was great 12 years ago when there wasn't anything else available but different story now.

As for the booster - hummm. Be a hard choice. Probably would have the original rebuilt and converted (or do it myself if I could find the parts). As Dave always mentions - that would be a bad choice in terms of repair costs and down time (points well taken) but it would be a little more original looking.

Second choice would be to hack the original booster off and use the OEM bracket with the new dual 8 inch booster. Either way - using the original pedal bracket to keep the pedal height where it is originally and not change the original pedal geometry.

On the British cars I grew up driving the brake pedal was always about 1/2 inch above the resting point of the gas pedal so that's where I feel comfortable with my brake pedal. I can't see how folks can drive some of the cars they have converted where the brake pedal is 6-8 inches above the gas pedal.

Not saying your build is wrong, the bracket will never work or anything like that - just sort of re-thinking mine.

As for how they would feel????

Never driven one with the Dual 8 inch booster although I'd like to just to see the difference.

My brakes feel a lot like the original drum set-up. Not light but not heavy either. Guess to compare it to something modern-ish it feels like the '96 Ford E150 Conversion/wheelchair van I used to have. Pretty much the same force needed to stop the van and my car now and the brake pedal is exactly where I like it.



(yes you can make fun of the old Firestone white floor mats my Dad bought 40 years ago I just recently replaced them with a set of the new style black ones)

Ok - enough rambling - better go get those Valentines Day flowers....

Eric

[simplyconnected]

Henry has some good ideas. We can all use more boost but there is such a thing as too much boost. I'm not saying his booster is too much because I never tried it.

All boosters require an initial pedal pressure just to open the valve in the booster. This includes the treadle-vac. Beyond that, things get different real fast. And remember, we don't always slam on our brakes but rather, we use only necessary pressure to come to a controlled stop.

In a manual brake setup, master cylinders don't determine brake pedal height, the pedal stop does. The Owner's Manual specifies certain 'jiggle room' for the pedal rod which shows the pedal and M/C are totally divorced.

Power brakes are slightly different because the pedal rod connects with thru-holes on both ends. The booster has a healthy spring that returns all the brake parts including the pedal, but that same booster is divorced from the master with the same 'jiggle room' and a jack screw for adjustment. It's that initial booster return-spring pressure that the pedal pressure must overcome before booster motion and assist happens.

All the ratios and linkage determines how the brake pedal feels. Again, we rarely use more than half of our braking hp but full capability must be sufficient to lock your wheels and it must be in reserve.

Is there enough boost? Test your brakes (with no one around) on dry pavement and do a panic stop at ~40 mph. If you cannot lock your tires there isn't enough boost. Do this on brakes that are 'bedded-in', not on brand new installations. My Scarebird/S-10 brakes on our Fordor Galaxie does lock the wheels using a dual 8".

When my brakes were manual (yes, that's how it came from Ford), standing on the pedal would not lock my wheels. By today's standards that's scary especially for women drivers. By 1959 standards, it was typical of all family size cars.

Eric, I wish we lived closer so you could drive my car. The power rack and pinion steering is great (especially in parking lots) and the power brakes easily stop 3,700-lbs.
BTW, your original firewall bracket already raised the booster enough. The 'dual-8' booster is the same diameter as yours but it is longer. Did you happen to save your original brake pedal rod? - Dave

[OX1]

First, my brakes are very easy for any lady to operate.

Next, I use the term "fulcrum" very loosely.

All motion from that bottom bolt is measured as an arc,
So how do you overcome this?- Dave

With a 5+:1 brake pedal ratio and dual diaphram booster,
I'm sure they are. For kicks I measured gas to brake
pedal and ratios of everything I own

vehicle-----------------gas to brake (in)-----------pedal ratio

70 Bronco
(orig man brakes,----- 5.25--------------------------6.5
now mustang HB)

79 Bronco---------------2.75--------------------------3.75

86 Capri 5.0------------2.75--------------------------4.3

03 EVO8------------------2------------------------------3.86
(AWD 4 cyl turbo jap
"supercar" with 4
wheel brembos)

05 Dodge 2500 diesel-----3----------------------------4.76
(7700 lbs curb weight)

14 Stang GT----------------2.5---------------------------3.8

15 Fusion AWD-------------2------------------------------3.2

14 Escape AWD-------------2.5----------------------------3.75

On average, my final pedal ratio of 3.19 seems a bit light,
but even back in 79, a power brake pedal ratio over 5
was probably excessive (again comparatively). Interesting
that my dodge has HB and a high pedal ratio, but @
7700 lbs, it needs all the help it can get I guess.

Yeah, I here ya. Classic, "fulcrum" or Class 1 lever, has
fulcrum in the middle, but a class two lever still has a
fulcrum, just not in the middle. If we called it Class 1 or
2 lever, no one would know what the heck we are
talking about



One of the side benefits of a big booster/MC, low pedal
ratio setup is reduced linkage motion. Minimizing
unintended vertical motions, on a vertically set up
pivoting linkage, that you want horizontal motion out
of, is easier if the linkage motion is short.

As anyone who has constructed any braking system,
almost from scratch, knows, it's one big compromise
after another (especially in these birds that nothing fits).
Ideally, we should be redesigning steering col/brake
pedal support and re-engineering brake pedal so you
don't need "fuclrum" setup for any reason. You'd
still need booster with a REALLY long rod, as there
is no good way to get booster near firewall with stock
shift linkage.

Anyway as mentioned, I highly prefer big
boost, short pedal travel, so that is what I shoot for.
You would think with a 6:1 pedal, Hydroboost and a
modified high pressure sag pump in my little bronco, it
would be "too much boost". But for me it's fine. I like
the fact I can modulate from light braking to lockup,
with very "fine" pedal inputs. Many others may hate
the low effort, short travel pedal, but I love it.

If I were converting today I would definitely go with the Scarebird brackets, rotors and calipers

On the British cars I grew up driving the brake pedal was always about 1/2 inch above the resting point of the gas pedal

Ok - enough rambling - better go get those Valentines Day flowers....

Eric

I'm keeping those brackets in mind as a backup in case
neither the 77 bird or Granada stuff I have works to
my liking. It could also get me a smaller caliper if I
feel I need it, after I get what I have now up and
running.

I agree, don't like huge distances between gas and brake
pedal. That said, I don't recall cursing my 70 bronco every
time I drive it and that is more than double most of
today's vehicles. I did not measure bird before pulling it
apart, but I'm pretty sure it is not over 5 inches.

How did she like the flowers???

In a manual brake setup, master cylinders don't determine brake pedal height

All the ratios and linkage determines how the brake pedal feels. Again, we rarely use more than half of our braking hp

If you cannot lock your tires there isn't enough boost.

If your booster rod is adjustable, you can set pedal
to your liking. As you said, this will affect overall
mechanics, by where you adjust pedal too. Whether
that brake pedal height affects brake feel or not, probably
matters less on pedal starting point, than it does on brake
pedal travel.

[simplyconnected]

...As anyone who has constructed any braking system, almost from scratch, knows, it's one big compromise after another (especially in these birds that nothing fits).
Ideally, we should be redesigning steering col/brake pedal support and re-engineering brake pedal so you don't need "fuclrum" setup for any reason. You'd still need booster with a REALLY long rod, as there is no good way to get booster near firewall with stock shift linkage...

...If your booster rod is adjustable, you can set pedal to your liking. As you said, this will affect overall mechanics, by where you adjust pedal too. Whether that brake pedal height affects brake feel or not, probably matters less on pedal starting point, than it does on brake pedal travel.

The bottom line is, whatever compromises you do, the M/C shall have full stroke capability. Otherwise your pedal will hit the floor before the piston stroke is fully extended. So, start from there.

The problem with Squarebirds is that the firewall M/C hole is too low. It's ok for a manual M/C, but any booster will hit the shift linkage. That's why Ford's firewall bracket raises the booster. Secondly, because it is raised, the link (your lever) needs room to move the booster input rod. That moves the booster away from the firewall.

Ratios were not that hard to figure given M/C stroke and pedal limits. You may have missed my point regarding placement of the bottom bolt on your bracket and how that also affects ratios.

The OEM setup used an offset pedal bolt to adjust the rod. That's why the hockey stick has fixed holes on both ends. - Dave

[OX1]

Think I am OK on pedal height, set it about 2-3 inches
above gas pedal (just intuitively). Does anyone know
what it is supposed to be stock (or can someone
measure?).

I was looking at the steer col/brake pedal bracket while
I was under the dash 100 times in the past couple weeks.
It does not appear that it would be that difficult to get
out if/when I wanted to modify it, but I might be
missing something on how it comes out.

I thought you were pointing out that when the
fulcrum rotates on either side of vertical (assuming
it points straight up), it will lose height as it rotates
and due to that, could affect pedal feel and/or
ratio (dynamically speaking). Yes??

I was wondering what that offset cam was. On my
parts car, it was loose. Must have made the pedal
height infinitely variable every time the brakes where
used . I assume it stays put due to friction when
tightened. I considered welding it in one place, but
maybe I'll leave it for additional adjustment.

The bottom line is, whatever compromises you do, the M/C shall have full stroke capability. Otherwise your pedal will hit the floor before the piston stroke is fully extended. So, start from there.

The problem with Squarebirds is that the firewall M/C hole is too low. It's ok for a manual M/C, but any booster will hit the shift linkage. That's why Ford's firewall bracket raises the booster. Secondly, because it is raised, the link (your lever) needs room to move the booster input rod. That moves the booster away from the firewall.

Ratios were not that hard to figure given M/C stroke and pedal limits. You may have missed my point regarding placement of the bottom bolt on your bracket and how that also affects ratios.

The OEM setup used an offset pedal bolt to adjust the rod. That's why the hockey stick has fixed holes on both ends. - Dave

[DKheld]

I'll measure the pedal height this weekend but won't be able to post until next week (darn secure areas).

My brake pedal is almost even with the accel pedal - that nice 1/2 inch higher that I like. Seems it's always been that way but the accel pedal is adjustable too.

That offset cam bolt does adjust the pedal but not by much - believe it was about 1 inch total. I just loved being upside down and backwards under there.

From this old pic you can see my cam bolt has a nut on the back - I put a star lock washer on it also - probably because I'm overly cautious. There is also a nylon ring that fits over the bolt and in the pedal. Keeps from having the metal bolt against the metal pedal and preventing wear I guess.



(and my firewall seal was slid all the way forward to the neutral safety switch in this pic so disregard that)

Eric

(oh - funny story on the flowers - stopped a a roadside stand that advertised doz roses for $9.99 - turns out they were small carved wooden roses "hand carved in Canada" for $9.99 the real ones were $24.95/doz. I opted for some real ones from another place - she liked them a lot. Almost bought the wooden ones just to give her and see the reaction but didn't feel like digging splinters out of my head after she hit me with them)