Trying to get better braking out of my 67 GTX 11” drums

[Butch Harley]

I put NOS on the front what a difference!!! Craig 516-485-1935

 

[WileE]

Craig at mobileparts = unequivocally endorsed

 

[ElectricBlue]

I have a 68 GTX that I got from another member. It has 11” drums and manual master cylinder. For him, it had great brakes. For me, I didn’t care for having to use both feet to get it to stop. I added a brake booster that helped, but not as much as I had hoped for. Then I installed a Granetelli vacuum booster. Now I have a brake system that performs as well as a modern vehicle.

 

[mrhemi]

This all is the reason that I switched to silicone brake fluid. Regular DOT 4 absorbs water/moisture and then leaking and destroying paint. But, it's your car.

I started using DOT5 silicone fluid 40+ years ago, and haven't looked back. My Charger R/T has had the same silicone fluid in it for all of that time with no issues. I have it in my old Mopars, boat trailers (surge brakes) and will be fill my wife's TR6 system with DOT5 as I finish that up.

 

[69_A12_6BBL]

This is becoming a long and expensive saga. Started out with noticing stopping power had gotten really sluggish in the car that had 100% of the brake system replaced 20 years ago. Just about the only used item was a booster I picked up. I installed brakes from the Praise Dyno Brake outfit back then which may or may not have become Muscle Car Brakes.

From a vacuum test, that I now suspect of being a bogus test method, I thought the booster had gone bad. I had the booster rebuilt by Harmon and reinstalled and no improvement.

Finally looked in brake master and the rear bowl was clear but the back bowl was brown, rusty mud. Tried to clean it out and the ports had been blocked to the front so no front brakes at all. Bought a new casting, correct style master and installed it after bench bleeding. Flushed the lines, got good clean fluid at all wheel cylinders and no leaks and firm pedal. Adjusted all wheels. Better breaking but still feels weak, especially compared to my 66 Satellite with the same 11” brakes, but no PB, and it stops very, very well. But I have no idea what brake shoes the PO put on it.

All lines are new, hoses were replaced, wheel cylinders were replaced. The Praise Dyno linings got roasted back 20 years ago due to not enough return of the Master Cylinder push rod. After figuring that out and adjusting I found some of the shoes were cracked. Praise Dyno said it wouldn’t hurt anything but now I’m not so sure.

So my next step would seem to be to try some new 11” shoes, but what type and brand? This is a cruiser and doesn’t get any severe use. I want a good shoe that works well cold and warm and I’m not sure if that should be organic or ceramics at this point.

Any suggestions?

Most of us just LOOK WAY AHEAD of where we're going. Know how the car handles. Prepare for either a Ditch or a Pole. NOT the car ahead of us IF we have to "Lose it"
Problem with changing out OEM stuff on a rare car is the PURISTS as myself who WON'T buy it if ya ever must sell it. Id DEFINITELY keep the Original parts.

 

[SlinktRR]

I find the OE 11" drums to be pretty stout when adjusted but yes you cannot drive them in traffic like it's a modern car. That doesn't stop me from driving in traffic I just drive differently. As long as mine stay cool, they stop well. 10" drums on the other hand...no thanks.

 

[1 Wild R/T]

Most of us just LOOK WAY AHEAD of where we're going. Know how the car handles. Prepare for either a Ditch or a Pole. NOT the car ahead of us IF we have to "Lose it"
Problem with changing out OEM stuff on a rare car is the PURISTS as myself who WON'T buy it if ya ever must sell it. Id DEFINITELY keep the Original parts.

Only car I have in my fleet that came with drum brakes I swapped to 11.75 discs, I have the stock drums spindles everything sitting in my storage... Anyone who buys it wants it stock they are welcome to swap it back... I drive my stuff... There are lots of stupid people on the road especially here in California, but I travel enough to know we haven't cornered the market on shitty drivers...

 

[Runcharger]

I've driven these cars alot. I find the 11 inch drums in good condition are just fine for one or two stops at say 70MPH and down. Above 100MPH they're not worth a pinch of... And if you're in modern traffic on a freeway and have to stop or slowdown quite a few times not so hot either. And if you want to drive it lots it's best to run manual adjusters and keep on the adjustment which could be a monthly or even weekly chore.
All in all, is it worth money and time to invest in them? Depends on where you live and how much you drive them.
(Hint), I had about 5 sets of the 11 inchers I lugged around for a few years, Now I have one set for "just in case" I find a worthy car that I restore and want to keep them on the shelf to go with the car in case I sell it. For me if I don't drive a car, I don't own it. Traffic only gets worse every year and the majority of cars on the road have better brakes and tires every year and drivers that are in their own world and will do panic maneuvers without warning anytime.
These cars can be stressful enough to drive witout worrying about outdated brakes. If you only drive it in and out of a trailer that's a different case.
I must say though I do find it alarming how many people have issues with brakes on these old cars, for gosh sakes if you're unsure of your brakes please find a professional that is versed in them and get the car repaired correctly.

 

[1KoolBee]

My Bee’s factory 11” brakes worked great at lower speeds, but as Runcharger stated, they totally suck above 70 in that they get hot and fade away around 40, then they are “2-footers”. A few years ago I installed a set of 11” ceramic/carbon shoes but I have not done a high speed panic test yet. I’ll post the results when I do. There’s plenty of deer willing to provide the opportunity around here.

 

[1 Wild R/T]

My Bee’s factory 11” brakes worked great at lower speeds, but as Runcharger stated, they totally suck above 70 in that they get hot and fade away around 40, then they are “2-footers”. A few years ago I installed a set of 11” ceramic/carbon shoes but I have not done a high speed panic test yet. I’ll post the results when I do. There’s plenty of deer willing to provide the opportunity around here.

And for the price of a replacement grill & header panel you could have disc brakes... But hey, you do you....

 

[1KoolBee]

And for the price of a replacement grill & header panel you could have disc brakes... But hey, you do you....

On this car ( probably 1 of 1, all numbers matching, original paint) I keep all mods stock appearing. So discs not an option. On my 67 GTX clone project, anything goes. It’s getting Cordoba cop car discs.

 

[1 Wild R/T]

On this car ( probably 1 of 1, all numbers matching, original paint) I keep all mods stock appearing. So discs not an option. On my 67 GTX clone project, anything goes. It’s getting Cordoba cop car discs.

So it doesn't get driven.... Cause if it does I would swap the brakes & keep the stock parts....

 

[68BabyBlue]

I have a 68 GTX that I got from another member. It has 11” drums and manual master cylinder. For him, it had great brakes. For me, I didn’t care for having to use both feet to get it to stop. I added a brake booster that helped, but not as much as I had hoped for. Then I installed a Granetelli vacuum booster. Now I have a brake system that performs as well as a modern vehicle.

I was used to really long stopping distances. The car stopped well compared to my daily driver.

 

[1KoolBee]

So it doesn't get driven.... Cause if it does I would swap the brakes & keep the stock parts....

The brakes stopped the car for 130k miles. I drove the hell out of it. Discs really not needed.

 

[Runcharger]

Thing is, you don't get a chance for a do-over. I remember my last trip up the Pacific Coast highway in a truck several years ago, I spotted a whisp of smoke about 1 mile ahead of me in traffic like this, I jumped on the brakes right away and it was still close getting it pulled down in time. If I had been even checking the mirrors it might not have turned out well. You have to give yourself every benefit these days, 40 years ago, no problem, everyone had the same brakes.

 

[1KoolBee]

True, but since I’m not a drunken 17 year old maniac any more, I figure my chances are pretty good with 11” drums and carbon ceramic linings. Night and day difference from stock.

 

[autoxcuda]

Location where you are driving is a factor.

I imagine Northern Idaho is much different than Southern California/LA

 

[1KoolBee]

Plenty of idiot drivers here, but biggest threat are deer, elk, and moose. Greatly reduced risk if you avoid dusk and dawn driving. Which in the summer, is like 4AM and 10pm.

 

[DeltaV]

The drum brakes provide the longer stopping distance you need for the idiot that rear ends you with his disc brake equipped car.

I would upgrade the exterior lighting before I upgraded the brakes. I don't plan on driving at night or in inclement weather. However, I want brighter tail/parking lights, brighter side marker lights, and brighter brake and turn signal lights for daytime driving.

 

[68BabyBlue]

Plenty of idiot drivers here, but biggest threat are deer, elk, and moose. Greatly reduced risk if you avoid dusk and dawn driving. Which in the summer, is like 4AM and 10pm.

Similar situation in central PA with the white tailed deer. When I used to drive that drum brake GTX to the Chrysler Nationals, with an early morning start, I'd detour through downtown, rather than expose myself to deer crossing the road by my development. I have power discs in the current car, but I still follow the same practice.