power brakes

[Doog 427]

Hi

Have 67 big block with manual brakes rear drum front disk, how much better would power brakes be? noticeable or very much better noticeable? Will car stop in shorter distance

TY
Steve

[shelbydoug]

Hi

Have 67 big block with manual brakes rear drum front disk, how much better would power brakes be? noticeable or very much better noticeable? Will car stop in shorter distance

TY
Steve

I at one time had gone to maual brakes on my 68 GT350. I don't remember the determining factor on making that decision.

Braking is just going to be a function of the components to your system. The power booster is really just a convenience thing. The car will stop exactly the same way with or without the power booster.

The biggest advantage was getting the Midland booster out of the way. Then there is much greater accessibility to the clutch linkage, #7 & #8 spark plugs.

I am back to power assist. I went with a Bendix booster which provides almost as much access as none.

The Midland just takes up way to much space for easy engine access.

[Side-Oilers]

In my experience, the car will not stop any shorter with PB.  The booster merely makes the pedal effort less.

But in a BB Shelby, the time it takes to change the spark plugs will be shorter with the manual master cylinder.

[The Going Thing]

Ford didn't offer manual disc brakes. I do note a difference in braking with power. As mentioned, 7-8 plugs or removal of the valve cover is more difficult with them.  The Midland-Ross booster works great when it is functioning properly. If you're considering the change over it's more complicated than a booster/master change.  You'll need the booster, master, distribution block, line kit, and residual valve. I am running Hawk Pads, which are helpful too.

[Side-Oilers]

I long ago removed the booster from my KR, because the cam didn't make enough vacuum to operate it...and thus was much worse than manual brakes as to pedal feel and modulation, IMO.

Plus, I actually prefer the feel of a good manual setup on a vintage performance car. So many of the factory PB setups from the '60s were waaayyyy over-boosted.

I'm currently running Wilwoods all around (6 piston up front) and 16-inch Specialty Racing Wheels five-spokers for clearance.  I've had the car on Willow Springs with the COCOA guys, and it has plenty of brake and a great firm feel. 

[shelbydoug]

You may want to sample dfferent master cylinders.

Stock it is 7/8" bore. I wound up with 1-1/8" bore with the manual setup.

What that does is makes it very difficult to lock up the brakes. That's one of the things race cars will do to make the car more race worthy.

It also reduces the travel distance of the brake pedal.

The smaller the bore, the more tendency to lock up the brakes.

Knowing what I learned from that excursion, I wound up with a 1" bore master with the power brakes. Don't be surprised if you go through several sizes before you determine what you like best.


Let me qualify what is in the car now. 67 "Big Ford" "Trans-Am" calipers and rotors (12 x 1-1/4 vented front, rear Lincoln Versailles. vented discs, Porterfield  street pads all around)

[Doog 427]

OK, thank you very much for replies understand and appreciate the feedback, Thank you

[The Going Thing]

I long ago removed the booster from my KR, because the cam didn't make enough vacuum to operate it...and thus was much worse than manual brakes as to pedal feel and modulation, IMO.

Plus, I actually prefer the feel of a good manual setup on a vintage performance car. So many of the factory PB setups from the '60s were waaayyyy over-boosted.

I'm currently running Wilwoods all around (6 piston up front) and 16-inch Specialty Racing Wheels five-spokers for clearance.  I've had the car on Willow Springs with the COCOA guys, and it has plenty of brake and a great firm feel.

I had intended to do a front upgrade with the so-called "Trans Am" change over.  They are factory components. Sadly, the information isn't widely shared of what can be used to make it work.  The 2200.00 price tag from Cobra Restorers is out of line for what it is. They also service rotors with non-factory parts. So it kills the reason for trying to stick with Ford components.