1966 c10 disc booster/mc upgrade list...

[fleetman]

my 66 came with hydralic booster option , can i just get the corvette style mc with proportioning valve and use the booster i have ?

another question. i see some propotioning valves (around 60$) that are only a brass block with a dial to regulate rear drum brake fluid pressure.... are these a must in addition to the proportion valve at the booster/mc ?

thanks
paul

[lolife99]

I would PM captainfab about your booster question,... or some of the guys on the 60-66 area.
A standard disc/drum or disc/disc prop valve should work fine.
The dial is usually found on "adjustable" prop valves,... and is used to "fine tune" the rear brakes.

[Captainfab]

I'm not sure I have ever seen a factory hydraulically booster master cylinder in a truck this old. Is this something someone has added at some time? All I have seen in the factory boosters is vacuum assisted.

You don't need a "Corvette" style master cylinder unless you are going with 4 wheel disc brakes

As for a proportioning valve, if you just have disc/drums, most any proportioning valve for a disc/drum system should work just fine. Now if you are going with discs front and rear, you can try a didc/disc proportioning valve, but you might find you need to fine tune the rear brakes. This can be done with an adjustable valve in the rear line. In light of this, you might consider the Wilwood proportioning valve that has a built in adjustable valve in the rear.

Originally Posted by fleetman

my 66 came with hydralic booster option , can i just get the corvette style mc with proportioning valve and use the booster i have ?

another question. i see some propotioning valves (around 60$) that are only a brass block with a dial to regulate rear drum brake fluid pressure.... are these a must in addition to the proportion valve at the booster/mc ?

thanks
paul

[fleetman]

thanks for the reply ....
yep mine is factory. the code on the glove box sticker says- J7OCG Hydralic Brake- it looks just like a regular booster with a one line master cylinder serving all 4 drums.
wondering what mc i can use if i retain my stock 'hydralic' booster ?
mine is just disc/drum...
thanks
paul

Originally Posted by Captainfab

I'm not sure I have ever seen a factory hydraulically booster master cylinder in a truck this old. Is this something someone has added at some time? All I have seen in the factory boosters is vacuum assisted.

You don't need a "Corvette" style master cylinder unless you are going with 4 wheel disc brakes

As for a proportioning valve, if you just have disc/drums, most any proportioning valve for a disc/drum system should work just fine. Now if you are going with discs front and rear, you can try a didc/disc proportioning valve, but you might find you need to fine tune the rear brakes. This can be done with an adjustable valve in the rear line. In light of this, you might consider the Wilwood proportioning valve that has a built in adjustable valve in the rear.

[Captainfab]

Well if you had a regular vacuum booster, I believe you can install a '71-'87 truck master cylinder. But I believe you will need to shorten the intermediate pushrod. I don't know just how much as I have not done this, I always upgrade to later model boosters. Once you upgrade to the dual reservior master you will have to split the lines and add a proportioning valve.. There is much more info on doing this over in the '60-'66 FAQ thread.

Originally Posted by fleetman

thanks for the reply ....
yep mine is factory. the code on the glove box sticker says- J7OCG Hydralic Brake- it looks just like a regular booster with a one line master cylinder serving all 4 drums.
wondering what mc i can use if i retain my stock 'hydralic' booster ?
mine is just disc/drum...
thanks
paul

[fleetman]

thanks - my booster is like new so i want to see if i can use it in front disc upgrade

[starvinartis]

That IS a vacuum booster, not hydraulic, otherwise it would have hoses running to it from the power steering pump

[Captainfab]

Have you seen a pic of what the OP has? I have not.

Originally Posted by starvinartis

That IS a vacuum booster, not hydraulic, otherwise it would have hoses running to it from the power steering pump

[starvinartis]

Post Number 4 above, OP states it looks just like a regular booster. A hydraulic booster by definition would have pressure lines to it as I said before and no vacuum drum.

BTW Captainfab, I have family and friends in Bonner and Boundary counties. Lived there myself. God's Country man.

[Captainfab]

Yes I did see that, but he keeps calling it a 'hydralic booster', so I'm wondering if he has something weird, or what.

Thanks for the compliment. Yeah I kinda like it here. Of course I take a lot for granted since I've been here for 40 years now.....wow that makes me sound old

[starvinartis]

I think it's the glove box sticker that's the confusion, if it had no power brakes it wouldn't mention any, the "hydraulic" just differentiates from an air brake set-up in my opinion. These same cabs as you know were used clear up to large diesel engine/tandem axle trucks. (7500 series ?). I had a 59 Ford 1 ton wrecker years ago ( but then we've all sinned @ one time or another lol ) with what appeared to be factory vacuum booster, only it was mounted on the side of the inner wheel housing, not behind the MC.
Fishing still good in Lake Coeur d'Alene?

[fleetman]

yep - what it says on glovebox sticker... J70CG Hydralic brakes .
there is a big partial pic of it in the 1966 supplement shop manual.
fig. 27 page 5-13.
that wedge/bracket at the firewall directs the booster and m/c towards the driver inner fender (in the engine bay).
i am not sure i will have clearance with a disc frontbrake m/c and proportioning valve if i use this booster with its shim bracket !
by clearance i mean the upgrade disc/drum m/c assemblys closeness to the inner fender...
i may try because the stock booster (drum/drum) is a newly rebuilt one.

anyway .... i wonder if someone else might have this option code and could chime in ... as to what they actually have !

[starvinartis]

Fleetman can you post a pic from that shop manual? Does the booster have pressure hoses attached to it somewhere or is it a vacuum line from the intake manifold, carb base, etc?

[fleetman]

sorry - not picture capable at the moment.
but it is a typical stock booster - single m/c for drum/drum.
no pressure hoses or anything fancy.
except the wedge/bracket affair at the firewall....
maybe someone could post that pic if they have a moment.

[starvinartis]

fleetman I dont know if the Vette MC will bolt right to your booster, I think most guys use 73-87 style set-up on those year trucks. I would ask Captainfab on that. I get what you mean as far as using yours since it is rebuilt, if the pushrod comes out the same distance as the Vette MC then all should be good. Luck!

[Captainfab]

I don't fish myself...too busy working 7 days a week. Some friends went out last week and caught some Blue Backs, said it was pretty good.

Originally Posted by starvinartis

I think it's the glove box sticker that's the confusion, if it had no power brakes it wouldn't mention any, the "hydraulic" just differentiates from an air brake set-up in my opinion. These same cabs as you know were used clear up to large diesel engine/tandem axle trucks. (7500 series ?). I had a 59 Ford 1 ton wrecker years ago ( but then we've all sinned @ one time or another lol ) with what appeared to be factory vacuum booster, only it was mounted on the side of the inner wheel housing, not behind the MC.
Fishing still good in Lake Coeur d'Alene?

[Captainfab]

It's beginning to sound to me like you just have the normal vacuum assisted brakes. I believe all cars and trucks have had hydraulic brakes since the late 30's.

If you are just running a disc/drum system, all you need is a master cylinder for a '71-'87 truck. However to use one with your original booster, I believe you will have to trim the intermediate pushrod. This is because the later model, disc/drum masters don't have the deep bore in the back of the master cylinder piston like your original master. I'm not aware of a disc/drum master with a deep pushrod bore, but someone else here may. While I have not used a stock booster with a dual reservior master, I do think there will be enough room. It will likely be tight though.

Originally Posted by fleetman

yep - what it says on glovebox sticker... J70CG Hydralic brakes .
there is a big partial pic of it in the 1966 supplement shop manual.
fig. 27 page 5-13.
that wedge/bracket at the firewall directs the booster and m/c towards the driver inner fender (in the engine bay).
i am not sure i will have clearance with a disc frontbrake m/c and proportioning valve if i use this booster with its shim bracket !
by clearance i mean the upgrade disc/drum m/c assemblys closeness to the inner fender...
i may try because the stock booster (drum/drum) is a newly rebuilt one.

anyway .... i wonder if someone else might have this option code and could chime in ... as to what they actually have !

[fleetman]

thanks captain.
i found a pic of my stock m/c , booster, firewall bracket set up.
there currently (today) is a post in the 66 era parts for sale section.
there are some great pics of a stock 283 engine bay. check out the brake assembly at the fire wall.
mine is identicle.
the original post i am refering to is posted by
Ronktonka for 66 283 forsale (originally posted 05-08-2012)

[Captainfab]

Yeah, that's just a regular vacuum booster. Nothing odd about it.

[fleetman]

Originally Posted by Captainfab

Yeah, that's just a regular vacuum booster. Nothing odd about it.

right. the booster, m/c are typical stock. but the horizontal off center bracket is the unusual component.
there is a way better pic of the bracket in the 1966 supplement truck shop manual.
page 5-13.
this bracket is what directs the booster, m/c towards the right inner fender.
just to clarify. thanks
paul