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Old 01-17-2019, 03:11 AM   #1
2bo.c10
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Upgrading Braking System

Hi Everyone

I want to convert my '58 to disc brakes in the front but I have a few issues and would like some help from the group:

1. I have a transmission which I dont believe will allow me to install the MC and brake booster that is needed. The truck started life as a 3-on-the-tree, but the gentleman who owned it before me changed it to a 3spd on the floor. I am not sure which trans he put in, but its not a great fit considering I cant connect my speedo cable because it gets in the way of the shift linkage.

Below is a note about the kit I want to buy and how it relates to the trans:

Note: Frame mount brake boosters may require #CP9424 transmission mount. May not work with manual transmission or stock wheels, please inquire. Kit uses 7/16 wheel studs. Booster will not clear stock clutch linkage

2. I dont mind mounting to the firewall (I know for some people this is sacrilege!) but I think I'd prefer it for ease of access. I realize though, that if I mount to the firewall, it changes the dynamic between the brake pedal and the master cylinder. If I were to go this route, how would I fix this Brake / MC connection problem?

3. Do I need a brake booster in order to run front disc brakes? Can I just have the disc set up, a master cylinder and a proportioning valve without the booster?

Thanks in advance!
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Old 01-17-2019, 10:49 AM   #2
Foot Stomper
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Re: Upgrading Braking System

Disc brakes require a booster as the master for the drum brakes didn't require as much pressure because of the way drum brakes are designed. The entire process of mounting a master on the firewall is a major mod and you are already asking the correct questions as there are many challenges.

Properly adjusted and maintained drum brakes work perfectly so there's no "need" for disc brakes. Hot topic, Im sure someone will tell me I'm wrong or old fashioned, but I can assure you that what I tell you is true.

My suggestion is you get the drum brakes in top shape, learn how they work, how well they work and keep your money for things you should pay more attention to. For example, replacing the wiring harness would be easy, and give more piece of mind than any disc brake conversion. There is a plug and play harness on the market for $300 that you could easily install in an afternoon. 60 year old wiring can burn that baby to the ground with no warning!
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Old 01-17-2019, 10:58 AM   #3
2bo.c10
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Re: Upgrading Braking System

Thanks for the reply-

Yes, I agree with you that drums work nicely when everything is replaced. Especially since itís not ABS I can see how ( I assume ) they work just the same. Iíve done the wiring in my previous build and it was fairly easy and I will likely do the wiring on this truck too.

Part of the reason I was going to do the disc conversion was because I need to replace the wheel cylinders up front and potentially more once I crack the drums open so I figured while Iím in there why not just do the disc conversion. If I love the MC to the firewall I know Iíll have to redo all the brake lines which Iím ok with, the part that Iím unsure of is the brake pedal/ MC connection. Before I make a decision, I want to find out more about this pedal/MC connection change.
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Old 01-17-2019, 04:36 PM   #4
Clarance J
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Re: Upgrading Braking System

Hello 2bo.c10. The answer to the second question in your third question is yes you can run a non booster MC with proportioning valve in stock location.
I have had this set-up on my 55.2 for several years now and have had no problems. You will need the adapter bracket that bolts the MC to the frame (either you fab or buy from one of the vendors). From my experience the pedal pressure is not very far away from stock. I got my MC/proportioning valve as one unit.
As to the shifter situation my truck came to me as a 6 cylinder and three on the column but I changed it over to a floor shift with a PEP boys Spark-O-matic shifter. That could be what the OP did.

So just a little bit more information on your search for answers.

Earl aka Clarance J
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Old 01-17-2019, 08:41 PM   #5
2bo.c10
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Re: Upgrading Braking System

Quote:
Originally Posted by Clarance J View Post
Hello 2bo.c10. The answer to the second question in your third question is yes you can run a non booster MC with proportioning valve in stock location.
I have had this set-up on my 55.2 for several years now and have had no problems. You will need the adapter bracket that bolts the MC to the frame (either you fab or buy from one of the vendors). From my experience the pedal pressure is not very far away from stock. I got my MC/proportioning valve as one unit.
As to the shifter situation my truck came to me as a 6 cylinder and three on the column but I changed it over to a floor shift with a PEP boys Spark-O-matic shifter. That could be what the OP did.

So just a little bit more information on your search for answers.

Earl aka Clarance J
Thank you! So youre running disc brakes in front, with no booster. Interesting. Wish I could use my stock MC as I JUST replaced it last month. I have yet to even put a mile on the truck using it....
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Old 01-17-2019, 10:32 PM   #6
1project2many
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Re: Upgrading Braking System

Quote:
Disc brakes require a booster
??

Plenty of disc brake cars were available with manual brakes. Manual disc master cylinder has smaller bore to increase mechanical advantage.

Quote:
Wish I could use my stock MC as I JUST replaced it last month.
You can, but...

It will be extremely important to select a front brake system which provides the right amount of braking on the front. With only one diameter bore in the master cylinder it's tough to figure out how much front braking is will be applied compared to the rear.

Last edited by 1project2many; 01-17-2019 at 10:42 PM.
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Old 01-23-2019, 03:02 PM   #7
roger55
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Re: Upgrading Braking System

Here's where I put my booster:

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