Disc Brake vs Drum Brake Pedal

customsportsman

customsportsman

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Hi everyone,
I am sure this question has been asked a bazillion times, but I cannot find a definite answer on the board. I have a 1969 Fury. Someone converted the thing to an aftermarket LEED brake system before I bought it. I hate the system. Last week, I got lucky and found a 72 Newport in a boneyard by me. I got EVERYTHING for a proper disc conversion, except I forgot to snag the brake pedal assembly.

Here is the issue:
1) I don't know for sure if my car was originally manual or power drum brakes. I suspect manual drum, as there was not a large vacuum port in the intake manifold for the booster when I bought it. Whomever added that aftermarket system, tapped off the PCV port for booster vacuum. I have since remedied the vacuum supply issue. Knowing this, and going on the fact that this car was most likely manual drum brakes originally, do I need a disc brake pedal assembly to achieve the proper pedal ratio when I convert this system over to the proper factory disc brake setup? OR, is my manual drum pedal assembly OK?

Thanks,
 
Just a thought here...

Any chance the fender tag is still there? If so, a B51 stamp would show power brakes.
 
A manual brake pedal on a power brake system will amplify the pedal input - not the worst thing - the reverse would reduce the pedal input (power brake pedal on a manual brake system).

You'll probably be OK, but if you've a chance, grab the pedal assembly as a spare.
 
Does this help at all? The first letter under that screw on the upper left is "R".


IMG_20230724_212215530.jpg
 
I forgot that I had the build sheet. here is a section that I blew up for the brakes. I'm no master at figuring out a build sheet, but I see nothing marked under the brakes. so does that mean standard which would have been manual drum?

Screenshot_20230724-213146.png
 
I don't see any code for power brakes, so most likely it didn't have them, but that's not written in stone either.

That doesn't mean that the pedal wasn't changed with the previous conversion.
 
Ross Wooldridge said:
A manual brake pedal on a power brake system will amplify the pedal input - not the worst thing...
Click to expand...
BTDT, back in 1992-1993. Gives a soft pedal (because the brakes are 'overboosted'), but car will stop just fine.


So @customsportsman -
What is it about the Leeds brakes that you don't like? Perhaps that can be corrected rather than putting factory discs on?
There are a number of reports that the Leeds booster is not a quality item.

BTW - the R11 on the fendertag is likely for the radio.
 
fury fan said:
There are a number of reports that the Leeds booster is not a quality item.
Click to expand...
From what I've seen, the Leeds (and others) booster/master cylinder are C3 Corvette based "one size fits all" pieces. IMHO, that's probably OK on the surface... But whatever you do, you are adapting it to fit. It just seems to me that using the Mopar pieces would be easier to use and everything "fits" without any added grief. The issues I read about look to be proper interfacing with the existing pedals. That may be "operator error" as some guys need to be reminded not to drink the brake fluid... Or it could just be a crappy design... Or a combination of both.
 
Someone asked me about what I don't like about the Leed system. The power brake booster is really bad. I have already replaced it once. The pedal does not properly come back up under certain conditions, and I don't think that there is enough boost by FAR. This unit is definitely chinesium. Most importantly, this system does not STOP the car under a hard stop like it should. I realize that this is not a new car. However, even with BOTH feet on the pedal, I cannot comfortably stop this barge. There is plenty of pedal, and I have adjusted the proportioning valve just to the point of preventing rear lockup. Upon looking at the system as a whole, the rotors seem to be too "light duty" for this application. In addition, I don't think there is enough braking surface area as compared to the stock system.
In conclusion, I would not buy this system. I will not give this system to someone else after I remove it from my car. I have been wrenching for 40 years, have had classic cars for most of those 40 years, and work in the automotive field. Therefore, I have the experience to say this....
If your car has the stock system (even if it is drums) keep it. Use common sense with the drums, and don't expect them to be like your 4 wheel disc daily driver. If you can find a complete STOCK disc system, get it.
These aftermarket systems are pretty, and under NORMAL circumstances are fine. But, after using this system, I suspect that under hard stop conditions, I will end up in the ***-end of whatever I am trying to avoid.
 
customsportsman said:
If your car has the stock system (even if it is drums) keep it. Use common sense with the drums, and don't expect them to be like your 4 wheel disc daily driver. If you can find a complete STOCK disc system, get it.
These aftermarket systems are pretty, and under NORMAL circumstances are fine. But, after using this system, I suspect that under hard stop conditions, I will end up in the ***-end of whatever I am trying to avoid.
Click to expand...
100% agree!!! Im curious about your brake pedal issue- differences??
 
66l78rat said:
100% agree!!! Im curious about your brake pedal issue- differences??
Click to expand...
Hey there (looks like you and I are neighbors. LOL). Understand that when I got the car, this system was already installed. The brake pedal issues are the following:

1) The pedal was 11 INCHES off of the floor. I was able to resolve that (somewhat). I have the pedal 7 inches off the floor now.

2) The pedal had a very large auxillary spring when I got the car on the pedal. Moving the pedal down helped somewhat, but the pedal still would not come back
to a full return point. LEED tech support suggested a new booster. I ate the 200 bucks and tried it. A little better but not much.

3) I had to install a bungee cord to get the pedal to come back to full rest so that the calipers will not drag.

4) Standing on the brake pedal, leads to a stop that is not comfortable.

5) Had I not found that disc setup of a scrap car, I was going to find all of the original drum parts and go back to them. All of my classics that I have had over the
years had drums, and I was fine with them.
 
Yeah neighbors and same taste for 69 Furys. My Fury is a non power drum car and they work great but require old fashion force and feel. My Polara is a power disc car that work great and are effortless. Point being there is no way I would go with aftermarket chinese made non factory C body brake parts.

IMG_0140 (1).jpg
 
customsportsman said:
Someone asked me about what I don't like about the Leed system. The power brake booster is really bad. I have already replaced it once. The pedal does not properly come back up under certain conditions, and I don't think that there is enough boost by FAR. This unit is definitely chinesium. Most importantly, this system does not STOP the car under a hard stop like it should. I realize that this is not a new car. However, even with BOTH feet on the pedal, I cannot comfortably stop this barge. There is plenty of pedal, and I have adjusted the proportioning valve just to the point of preventing rear lockup. Upon looking at the system as a whole, the rotors seem to be too "light duty" for this application. In addition, I don't think there is enough braking surface area as compared to the stock system.
In conclusion, I would not buy this system. I will not give this system to someone else after I remove it from my car. I have been wrenching for 40 years, have had classic cars for most of those 40 years, and work in the automotive field. Therefore, I have the experience to say this....
If your car has the stock system (even if it is drums) keep it. Use common sense with the drums, and don't expect them to be like your 4 wheel disc daily driver. If you can find a complete STOCK disc system, get it.
These aftermarket systems are pretty, and under NORMAL circumstances are fine. But, after using this system, I suspect that under hard stop conditions, I will end up in the ***-end of whatever I am trying to avoid.
Click to expand...
I was wondering if they used another "one size fits all" approach to the brake sizing.

It always seems to me that when it comes to Mopar fitment with a lot of these products, they assume that because it fit a '67 Coronet, it would fit everything Chrysler made in the 60's and 70's.
 
66l78rat said:
Yeah neighbors and same taste for 69 Furys. My Fury is a non power drum car and they work great but require old fashion force and feel. My Polara is a power disc car that work great and are effortless. Point being there is no way I would go with aftermarket chinese made non factory C body brake parts.

View attachment 608047
Click to expand...
Nice. Your vert must be a cousin of Shamu, my vert:

IMG_3322.jpeg
 
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