Disc conversion question

[two-bit]

Reading thru the write-up Kieth has done. Top notch i believe.
Saw in the list of things to grab, it said master cyl. and booster.
Do i have to use the master cyl. and booster from the parts truck? or can i just use my own.
My 72 already has the booster, and a new master from a few months ago.

Just wondering, maybe there is a difference between the 72' master and the 79' master? I thought they were the same?

Anybody help me out here?

Two-bit

[FORDification]

Your existing booster will work, but you will need the master cylinder. Disc brake master cylinders are different than drum brake master cylinders. Also be sure to get the disc-brake proportioning valve to replace the drum-brake distribution block.

[two-bit]

Thanks Kieth
Two-bit

[71 LONG BED]

Check out Steve's post, too, Tony. He did some "research" this weekend on his. Before you start taking everything apart, you may be interested in what he found out.

Here is the link to the thread he started.

[FLATBEDFORD]

I was wondering about the booster too. I'd like to use the one I have too. That would be one more step to simplifying the conversion.

[hookman]

Just read the drum to disc conversion for f-100, it was said where you bolt tie rod end to the spindle on 73 and up is thicker than the 72. Can i just use the all 73 steering components from the pitman arm down on my 72. Just collecting parts now still dont know how to post pics yet, hope to get to soon.
GGGGGGGGreat site!!!!!!!!!!

[fordman]

yes

[FORDification]

Yep, the best thing to do is to use the entire '73 front end, to include the steering box and all linkage, and the I-beams and everything outboard of that. Don't forget the disc-brake master cylinder and the disc brake proportioning valve, to replace the drum-brake distribution block. Everything is a 100% bolt-up, except for the minor fabbing of brake lines.

[hookman]

My 72 has power brakes and power steering gearbox already, donor 73 does'nt have power brakes or steering. Can i ues the master cyl off a non pwr brake 73 on a 72 power booster. Or just buy a new one. What about non power steering gearbox pitman arm, will it bolt on a power steering gearbox from a 72? The 73 does have disc brakes hope to use on 72.

[FORDification]

Sorry, I missed it that your truck was a '72. Your '72 box actually should already have the correct Pitman arm, if the brake setup is factory. Take a look at the following pic...you want the one on top, with a D2 casting number:

http://www.fordification.com/images/FAQ ... arison.jpg

(The bottom Pitman arm in that picture has a C9 casting number.) Your truck should also already have the correct steering linkage to work with the thicker steering arm of the '73 disc-brake spindle.

The master cylinder doesn't care if it's bolted to the firewall or to the power booster...there's no difference between them. There IS a difference between drum- and disc-brake units. And yes, it'll bolt up to your existing booster.

If you haven't already seen the following page, it's worth checking out:

http://www.fordification.com/str-susp_variations.htm

[hookman]

thanks,ya'll are a lot of help.

[71 LONG BED]

...you will need the master cylinder. Disc brake master cylinders are different than drum brake master cylinders.

My '67 was converted tp power brakes somewhere along the line. It still has 4 wheel drums. My question is, does the master cylinder need to changed or can you just throw a booster behind the master that is already there? If you are keeping the drums, that is.
I'm asking because, even though I can stop the truck, I can't stop it that quickly. I definitely need to get in there and inspect the system. I was just wondering if that could be one of the reasons that the braking is less then perfect.

[fordman]

the masters are the same for manual and power for drum brakes all the way around.

[71 LONG BED]

Thanks fordman. I'm just trying to narrow down my search as to where the problem lies with the brakes. Hopefully it will be nice next weekend so I can take a look at the front brakes. I figure I'll start there.

[theskytoucher]

Your problem could lie that it is just a really heavy truck on drum brakes!!!! BUt ya never know