The Stovebolt Site Forums The Shop Area Engine Shop Brake Upgrade to a Dual System ?

I've looked at a few topics and can't seem to get the questions answered on this as of yet.

I've been told by all my friends (who like me) that I should change the single master cylinder brake setup I have on the '60 GMC to a dual cylinder setup.

As I understand it this would seperate the front and rear brake system into 2 different sets of lines so that if one wheel cyclinder fails, I would not lose brakes to all 4 wheels. Sounds like a great idea!

I will "assume" that this will require a valve of some sort to send differents amounts of pressure to the brake systems.

However, I do not know what to ask for in a dual master cylinder or what year. Or any other parts for that matter. I read "Cletis's" write up,

http://www.stovebolt.com/techtips/master_cylinder/index.html

on a change over but am unsure if this can be done on my '60 GMC. Has any of the members made the change and can you give some pointers?

Thanks
Jake

Classic Performance Products carries a large inventory of brake upgrades for your 60 GMC.
Their bolt-on dual MC with booster comes with a proportioning valve built in.

http://www.classicperform.com/6092chevtrk.htm

Thanks
I'll give them a call tommorrow, I see the kits but they state Disc/Drum, Not Drum/Drum. I don't know if they make a differance.

Jake

Jake - If you still have drum brakes on all four wheels, no valve of any kind is needed. Get a new M/C with the same bore as your existing one & it'll have the same stroke & pedal 'feel' when you stop. Your local NAPA can find one in their paper catalog. A bit of fab. work & you can make a adapter bracket to mount it on your truck. Make a pushrod of the proper length & get some new lines & re-plumb it to split the front & rear & you're done. Doug

Jake,
I concur with Doug. Granted, the 6400 I have is 7 years older than your truck, but it's still got 4 corner drums and I didn't have to install a proportioning valve of any kind. We wound up taking the power brake system off an 81 1-ton Chevy Suburban and fabricating a bracket for it to mount it under the cab and we just plumbed new lines and ran them. It was nice because the truck originally had a hydrovac and the M/C was a power unit, so it still stops extremely well. It was definitely worth the minor hassle. -Jake Schaeffer

The purpose of the proportioning valve is to engage the rear brakes before the front. This valve should be part of the MC on a dual system. I assume it would be beneficial on drum/drum systems. I don't know if the 60 GMC had a booster ( if I remember correctly, they were beginning to be installed in some vehicles about that time tho my 1960 Ford truck didn't have one) but I would guess you would want one.

Big Chevy,

No it did not come with a booster and I'm at a lost as to what to ask for. I'll stop by NAPA and speak to one the old timers and explain the situation.

Ok,

I called CCP (almost typed CCCP, bad ole days) Here is what they recommended. The picture shows a proportioning valve, but the kit does not need it, so you don't get it. With shipping it is $332.00.

http://www.classicperform.com/Store/1960_1972_Chevy_Truck/6062BB2.htm

I explained that I would not like to use the booster, to try to keep close to the OEm look, they said it was not required, but recommended for stopping power.

Restoring is a great and honorable goal and one I have in the past attempted. However in any area where I can improve safety I will overlook originality in favor of safety. Jake, get the booster! Now, I've done my duty...