Bullnose Enthusiasts Forum

Newer Style Master Cylinder Swap

Classic

List

Threaded

69 messages Options

1234

Machspeed

Newer Style Master Cylinder Swap

Administrator

I'm seriously considering a newer style master cylinder swap on my truck. I know Cory and Gary have made this swap, both addressing it in slightly different ways using different year OEM style master cylinders.

That said, I'm trying to figure out what year OEM style Master cylinder would be best for my truck giving me full capability and utilizing my OEM Booster and proportioning valve. I want for my brake light to work and I'm not exactly sure how that's all wired in! I've not looked yet but I know there is no wiring going to my OEM master, while wiring does go to the upgraded master. Suspect electrical signals sent via the proportioning valve in my trucks current OEM state??? I understand I will have to reverse lines and I'm fine with that. In fact, I will likely make new lines with copper nickel brake lines....easy to bend and flare.

I'd appreciate advise on this and any other input I may be overlooking.

Thanks!!!

John

"Blackie" - 1986 F150 4x4 - Mildly warmed over 351W HO - Original owner

Gary Lewis

Re: Newer Style Master Cylinder Swap

Administrator

The proportioning valve grounds a wire to light the BRAKES light on the dash when the balance between the front and rear is upset, like if you blow a hose on one side or the other. So if you go with a later master and retain the proportioning valve you won't need to change any wiring.

And if you make your own lines you won't need the residual pressure valve that adapts the existing front line to fit the master. But, it won't hurt to have that valve and then you wouldn't have to make lines, find the right fittings, etc. Or, you could do like I did and use 1990ish lines. Those trucks still had the proportioning valve but went to the later master, so screw right in to the proportioning valve you have an a later master.

But some of the later master cylinders have a port in them for a switch. You don't need that port nor switch, but if you get a master with one then I'll send you one of these brass plugs. I bought 10 and there are now 9 in there after I used one on BB's master cylinder. Would love to farm them out.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

Rembrant

Re: Newer Style Master Cylinder Swap

Gary Lewis wrote

And if you make your own lines you won't need the residual pressure valve that adapts the existing front line to fit the master. But, it won't hurt to have that valve and then you wouldn't have to make lines, find the right fittings, etc.

Gary,

Do you have the residual pressure valve installed? I didn't think it was possible to go without it?

1994 F150 4x2 Flareside. 5.0 w/MAF, 4R70W, stock.
1984 F150 4X2 Flareside. Mild 302 w/ 5spd. Sold.
1980 F150 4X4 Flareside. 300i6 w/ 5spd. Sold in 2021.
1980 F100 4X2 Flareside. 351w/2bbl w/NP435. Sold in 1995

85lebaront2

Re: Newer Style Master Cylinder Swap

Administrator

In reply to this post by Gary Lewis

If you order the MC for without cruise or the pre-1993 cylinder there is no extra port. I used one for with cruise as I needed the extra port for my trailer drake controller.

Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

Machspeed

Re: Newer Style Master Cylinder Swap

Administrator

In reply to this post by Rembrant

Rembrant wrote

Gary Lewis wrote

And if you make your own lines you won't need the residual pressure valve that adapts the existing front line to fit the master. But, it won't hurt to have that valve and then you wouldn't have to make lines, find the right fittings, etc.

Gary,

Do you have the residual pressure valve installed? I didn't think it was possible to go without it?

I noted that in your thread Corey and I'm glad you brought that back up. I await Gary's response on this.

Bill thank you! I was perusing through Rock Auto looking at MC's and wondering why cruise made a difference.

So gentlemen, if I order an 87 MC spec'd for like truck to my 86 (351, 4x4, etc) , I should have no issues?

John

"Blackie" - 1986 F150 4x4 - Mildly warmed over 351W HO - Original owner

Gary Lewis

Re: Newer Style Master Cylinder Swap

Administrator

In reply to this post by Rembrant

No, Cory, I don't have the residual pressure valve. That is Huck's 1990 lines, which screwed into the '95 master cylinder on the top end and the Bullnose proportioning valve on the bottom end. No need for a residual pressure valve to adapt the fitting sizes.

Gary, AKA "Gary fellow": Profile

Rembrant

Re: Newer Style Master Cylinder Swap

Gary,

That master has the residual pressure valve, circled in yellow. Is that not what that valve is? That is what I have been calling it. There is no way to connect a brake line without it.

Gary Lewis

Re: Newer Style Master Cylinder Swap

Administrator

Well, I'll be a .....

How did I miss that? I was thinking that valve was in the front. Boy, I'm embarrassed!!!

Cory, thanks for correcting me. Good catch.

Gary, AKA "Gary fellow": Profile

Rembrant

Re: Newer Style Master Cylinder Swap

Gary Lewis wrote

Well, I'll be a .....

How did I miss that? I was thinking that valve was in the front. Boy, I'm embarrassed!!!

Cory, thanks for correcting me. Good catch.

Ha, it's nothing. The reason I'm such a stickler about that residual pressure valve is that it was a bit of an issue for me initially. I kept reading that in swapping the later master cylinder on, nothing else was required (as in, no extra parts). That IS true if you go to the junkyard and grab a master cylinder from a later truck. However, if you do like I did an buy a later master cylinder, that residual pressure valve is not included with it. All you get is a new o-ring to swap the old one over to the new master.

The good news is that the residual pressure valves are easy to find at the junkyard, and easy to remove. All you need is something to cut the brake line with, and an adjustable wrench to remove the residual pressure valve (if you are not taking the whole master complete, like some do).

Here is what it looks like all alone:

In any case, back to John's questions:

I bought a new master cylinder for a 1991 F150. As a general rule of thumb, when buying "upgrade" parts for the later trucks, I typically try to stick within the Bricknose 1987-1991 years as there were some changes in 1992 that may or may not be compatible. 1991 is my go-to year.

The later master cylnder bolts directly to the Bullnose booster, no problem. I did have to adjust the booster pushrod slightly, but that's it.

The lines are reversed front to rear as noted previously.

The wiring. I was gutting my entire brake system at the time, so my old prop valve was removed and discarded. This is why I connected the old wiring to the new master cylinder.

Technically you could wire them both in if you wanted to (I think). That way you get the brake warning light to also illuminate if your brake fluid gets low.

Machspeed

Re: Newer Style Master Cylinder Swap

Administrator

Corey, that's great information, thank you! Need just a little more though, at least for me, I'm slow!

It seems I read somewhere that the use of the residual pressure valve is no more than an adapter. The post I read stated that and, in fact, the guy took the guts' out of it to utilize it merely as an adapter. I believe I read that here: https://www.ford-trucks.com/forums/1493345-swap-to-newer-style-mc-2.html

Thoughts on this? If it's not merely an adapter for our purposes, why is it needed in the conversion when the OEM unit (cast unit) does not utilize one?

John

"Blackie" - 1986 F150 4x4 - Mildly warmed over 351W HO - Original owner

Rembrant

Re: Newer Style Master Cylinder Swap

Machspeed wrote

Corey, that's great information, thank you! Need just a little more though, at least for me, I'm slow!

It seems I read somewhere that the use of the residual pressure valve is no more than an adapter. The post I read stated that and, in fact, the guy took the guts' out of it to utilize it merely as an adapter. I believe I read that here: https://www.ford-trucks.com/forums/1493345-swap-to-newer-style-mc-2.html

Thoughts on this? If it's not merely an adapter for our purposes, why is it needed in the conversion when the OEM unit (cast unit) does not utilize one?

I guess it depends on the situation. Since I removed the factory valve on the frame of my truck, I actually need the residual pressure valve on the later master, so for me it is more than an adapter. The purpose of the residual pressure valve is to keep about 10psi pressure on the rear brakes. Otherwise, the drum brake springs would overcome the brake fluid and push it back to the master...which in turn would cause me to require more brake pedal travel to activate the rear brakes.

The factory proportioning valve on your frame serves this purpose. It serves a couple purposes, but one is that it has a prop valve for the rear drum brakes. If you are leaving it intact, then I guess you don't need the residual valve on the master cylinder, except to use it as an adapter.

It looks like Gary has both installed, unless he also gutted the residual pressure valve?

I don't know if that answers your question or not. You don't need both, but you definitely should have at least one or the other installed.

PS: I have read where guys have swapped the later masters in (and nothing else) and reported no issues, so having both installed maybe isn't a problem? I don't know.

Gary Lewis

Re: Newer Style Master Cylinder Swap

Administrator

I have both, the one on the frame and the one on the master. And I have no braking problems. The brakes work very well.

Gary, AKA "Gary fellow": Profile

Machspeed

Re: Newer Style Master Cylinder Swap

Administrator

Thank you gentlemen, appreciate ya. I did a Rock Auto search on 91 F150 and came up with a Motorcraft Master Cyl that appears to have that residual pressure valve. I may go with it.

https://www.rockauto.com/en/moreinfo.php?pk=1832506&cc=1121982&jsn=1458&_nck=ZExt1ysfqhqWnq%2BEvUNdS3Txyey60IDtnjPWF5UU9J0BWQv7pvqZbkEUk86%2BAYIhteHnM8iYlR42ABYumiydqeDsVaKATbzthYoKxu7WdO3L0RLABETRJS3oXrKgETnvdclw0V5gXaS0MFv%2BoNr49Ml6Y7r4yquuS%2FERxIG46x%2BToE7K7F58lfRhGFUdcmPnS%2F74O6ZDMmPFyDNAZbVRh9oioas0VZw0oEh8UvV7z6yUYko4wE3QumAN4QEBZAQpH0l14gD2ssYRuwv4YFYXdxBe6tZrZoejJdn74kljGza1RTJWu8VgJrxBymv0V8pfgHcpJZjEzKIsdLFjgiY7Aa5Q9WkR9G14&jsn=1458&_nck=ZExt1ysfqhqWnq%2BEvUNdS3Txyey60IDtnjPWF5UU9J0BWQv7pvqZbkEUk86%2BAYIhteHnM8iYlR42ABYumiydqeDsVaKATbzthYoKxu7WdO3L0RLABETRJS3oXrKgETnvdclw0V5gXaS0MFv%2BoNr49Ml6Y7r4yquuS%2FERxIG46x%2BToE7K7F58lfRhGFUdcmPnS%2F74O6ZDMmPFyDNAZbVRh9oioas0VZw0oEh8UvV7z6yUYko4wE3QumAN4QEBZAQpH0l14gD2ssYRuwv4YFYXdxBe6tZrZoejJdn74kljGza1RTJWu8VgJrxBymv0V8pfgHcpJZjEzKIsdLFjgiY7Aa5Q9WkR9G14&jsn=1458&_nck=ZExt1ysfqhqWnq%2BEvUNdS3Txyey60IDtnjPWF5UU9J0BWQv7pvqZbkEUk86%2BAYIhteHnM8iYlR42ABYumiydqeDsVaKATbzthYoKxu7WdO3L0RLABETRJS3oXrKgETnvdclw0V5gXaS0MFv%2BoNr49Ml6Y7r4yquuS%2FERxIG46x%2BToE7K7F58lfRhGFUdcmPnS%2F74O6ZDMmPFyDNAZbVRh9oioas0VZw0oEh8UvV7z6yUYko4wE3QumAN4QEBZAQpH0l14gD2ssYRuwv4YFYXdxBe6tZrZoejJdn74kljGza1RTJWu8VgJrxBymv0V8pfgHcpJZjEzKIsdLFjgiY7Aa5Q9WkR9G14

John

"Blackie" - 1986 F150 4x4 - Mildly warmed over 351W HO - Original owner

Rembrant

Re: Newer Style Master Cylinder Swap

Machspeed wrote

Thank you gentlemen, appreciate ya. I did a Rock Auto search on 91 F150 and came up with a Motorcraft Master Cyl that appears to have that residual pressure valve. I may go with it.

Well boom, there you go. I bought mine locally from CarQuest, and it didn't come with the valve. If it's included, then all the better, Nice find. If you can move your existing lines around, it's a pretty straight forward install.

Gary Lewis

Re: Newer Style Master Cylinder Swap

Administrator

In reply to this post by Machspeed

Yep, looks like a perfect fit to me. You'll have to finish out this thread when you install it. And, maybe write it up in Upgrades?

Gary, AKA "Gary fellow": Profile

Frogger2662

Re: Newer Style Master Cylinder Swap

In reply to this post by Machspeed

Looking at Rock Auto for a 1990 f150 they list a Motorcraft master cylinder with what looks like the valve ya'll are talking about. Is this the valve?
BRMC 63 is their part number.

1984 F150 Flareside
1992 stock 5.0 with edelbrock 4 barrel.
Dual exhaust.

Machspeed

Re: Newer Style Master Cylinder Swap

Administrator

Exact same MC as the one I posted earlier for a 91. Yes, that's the valve.

John

"Blackie" - 1986 F150 4x4 - Mildly warmed over 351W HO - Original owner

Frogger2662

Re: Newer Style Master Cylinder Swap

In reply to this post by Machspeed

So if i am understanding this i can use this on my 84 f150 just by swapping brake lines from front to rear? Thread sizes the same?

1984 F150 Flareside
1992 stock 5.0 with edelbrock 4 barrel.
Dual exhaust.

Machspeed

Re: Newer Style Master Cylinder Swap

Administrator

As I understand it, the unit can be used and you will have to swap the brake lines. I cannot vouch for the fittings though.

John

"Blackie" - 1986 F150 4x4 - Mildly warmed over 351W HO - Original owner

Rembrant

Re: Newer Style Master Cylinder Swap

In reply to this post by Frogger2662

Frogger2662 wrote

So if i am understanding this i can use this on my 84 f150 just by swapping brake lines from front to rear? Thread sizes the same?

Hey Frogger,

I have one in my 1984 F150, and I'm almost positive that the fittings are the same, but I did not do a direct swap. When I was rebuilding my truck and fixing up the frame, etc I ripped out all of the brake lines and original master cylinder. I didn't install the new one until several months later. I made all new lines, but I'm pretty sure I re-used the larger of the two fittings because I didn't have a new one, and the other fitting is just one of the regular sized 3/16" brake line fittings.

I did read just recently that a guy went to the junkyard and grabbed a later master cylinder, and all he had to do was reverse his original lines, and everything bolted in place no problem. Take that with a grain of salt, but I'm pretty sure the fittings are the same, just reversed for front and rear.

I can measure the hex of the fittings if it would be any help.

1234