No power drum brakes???

-
rtse66

rtse66

FABO Gold Member
FABO Gold Member
Joined
Dec 20, 2008
Messages
364
Reaction score
146
Location
sunny warm minnesota
Just bought a 68-70 ish a body power brake booster. He said it's a 7 inch. So I asked if it was off a disc or drum brake car and his reply was you couldn't get power drums on an a body....huh?
Is this true? I have seen power drum brake cars but they were B,C, or E bodies
 
Nope. Plenty of them came with power drum brakes.
 
rtse66 said:
Just bought a 68-70 ish a body power brake booster. He said it's a 7 inch. So I asked if it was off a disc or drum brake car and his reply was you couldn't get power drums on an a body....huh?
Is this true? I have seen power drum brake cars but they were B,C, or E bodies
Click to expand...
I have two 65 Dart with 273 hp and power 10' drum brakes.
 
Yeah, he's full of hooey. Probably more power drum cars than factory power disc.
And don't worry about what yours was, same booster either way.
 
My 68 Dart GT convertible had power drum brakes, I finally took the power unit off after I put a MP crate 360 in it and there was not enough vacuum to operate them after several attempts at using accumulators...
 
Any more info on this would be appreciated.

IMG_20231013_152731030.jpg


IMG_20231013_152746270.jpg


IMG_20231013_152755004.jpg


IMG_20231013_152801971.jpg
 
I guess when all else fails... Midland Ross....but it looks a little different. Maybe a little later than 68.

16972315112698080605951748221489.jpg
 
Manual brake cars (drum/drum) can benifit from switching to a 15/16" master cylinder.

This gives more leverage at the pedal and makes it feel more like power brakes with more control to boot.

Without the bulk of the power brake unit and the need for vacuum besides.

Screenshot_20231011-072758_Gallery.jpg


☆☆☆☆☆
 
rtse66 said:
Any more info on this would be appreciated.

View attachment 1716153471

View attachment 1716153472

View attachment 1716153473

View attachment 1716153475
Click to expand...
that is indeed the "early" booster. the later one is flatter (narrower?) and a little larger diameter.

the bracket is very similar, but i think there is a subtle difference in distance/angle from the lower pivot to the face. i'm not 100% on that, it could just be the angle/lighting-- i'm basing it off the later set up that i have sitting here on the bench.

for all intents and purposes, they'll bolt up and work the same from 67 and up.
 
Somehow, this came into my possession and I have no idea what it originally fit...


IMG_E2302.JPG


IMG_E2304.JPG


IMG_E2306.JPG
 
I had the same Midland Ross booster in my '71 Demon
Unfortunately, it broke down some months ago and impossible for me to locate another one...

I have had to replace it with an universel combo MC/booster kit :(
Brake booster.jpg

BB 800x600.jpg
 
George Jets said:
Manual brake cars (drum/drum) can benifit from switching to a 15/16" master cylinder.

This gives more leverage at the pedal and makes it feel more like power brakes with more control to boot.

Without the bulk of the power brake unit and the need for vacuum besides.

View attachment 1716153578

☆☆☆☆☆
Click to expand...
Does the brake cylinder bore size have any impact? I see options for 13/16" and 15/16" bore size for the brake cylinders.

2nd question: Why are there different master cylinders for 9" and 10" brakes but the bore size is different. MC36338 says it is for 9" brakes....
 
Last edited:
shep76 said:
Does the brake cylinder bore size have any impact? I see options for 13/16" and 15/16" bore size for the brake cylinders.

2nd question: Why are there different master cylinders for 9" and 10" brakes but the bore size is different. MC36338 says it is for 9" brakes....
Click to expand...

The theory it is the Fulcrum and the Lever.

Moving the Fulcrum farther away from the lifting point increases the lift range and it takes more exerted effort to lift it. > Larger Cylinder Bore.

Moving the Fulcrum closer to the lifting point decreases the lift range, but in turn decreases the required exerted effort to lift (move) the work. > Smaller Cylinder Bore.

The smaller cylinder bore will have a longer stroke but an easier more controlled push on the brake pedal.

Smaller diameter brakes in theory use smaller wheel cylinders, so requires less fluid pumped to actuate the brakes.

B Bodies have larger diameter brakes, so they originally came with the larger diameter bore masters.

All else fails call Dr. Diff as he has working solutions available.

☆☆☆☆☆
 
You must log in or register to reply here.
-

Back
Top