The Elephant In The Room: unloading the load from a B-body.

[fullmetaljacket]

Ok, I have the write up and I am just getting pictures together. You can chew on this to start:
Getting a pair of aluminum rear wheel cylinders is possible but you will need to get creative with some of the pieces.

Parts list:

For 13/16” bore wheel cylinders:

• (2) Dorman W37696 wheel cylinder
• (2) Dorman W120343 wheel cylinder
• (4) 6mm-1.0 metric bolt 10 mm in length

For ¾” wheel cylinders:

• (2) Dorman W37863 wheel cylinders
• (2) RAYBESTOS WC370178 wheel cylinder
• (2) Brake Line Adapter 3/16 SAE Inverted Flare 10mm x 1.0 Male Bubble
• (4) 6mm-1.0 metric bolt 10 mm in length

For those of you keeping track, here are the overall weight differences.

13/16” applications:

• Cast iron wheel cylinder:
  • 19.34 ounces (each)
• Aluminum wheel cylinder:
  • 8.74 ounces (each)
• Weight savings:
  • Each: 10.6 ounces
  • Total: 21.2 ounces (1.325 pounds)

¾” applications:

• Cast iron wheel cylinder:
  • 19.6 ounces (each)
• Aluminum wheel cylinder:
  • 7.43 ounces (each w/brass adapter)
• Weight savings:
  • Each: 12.17 ounces
  • Total: 24.34 ounces (1.52 pounds)

You can get a little extreme and save another ounce or two by using titanium bolts and bleeder screws (they are available).

Badvert. With a smaller bore compared to the 15/16 bore of a Mopar unit, will the pressure at the rear wheels be less?

 

[fullmetaljacket]

View attachment 1717961

What are we looking for in this Rem? Are those pinched continental shelves gone?

 

[RemCharger]

What are we looking for in this Rem? Are those pinched continental shelves gone?

Yes sir. Iirc it went from 38 to 22. But it's getting close to 20 years ago now..
Took out some unnecessary gusseting as well

 

[fullmetaljacket]

Yes sir. Iirc it went from 38 to 22. But it's getting close to 20 years ago now..
Took out some unnecessary gusseting as well

Dammn, that's a good fat trim if I ever seen one. Wish I would have done it, but I was impatient. I did get rid of the motor mounts and some gussets though. Next time I have either the engine and or ignition system out of the car, I'mma going trimming and sealing. Much better either when the K is off the car or on a lift with a good Tig welder juiced on the side.

 

[Badvert65]

Badvert. With a smaller bore compared to the 15/16 bore of a Mopar unit, will the pressure at the rear wheels be less?

I think the pressure would be less. I have front disk brakes and there was a service bulletin about using smaller wheel cylinders on the rear drums. Smaller than the original 15/16" ones. Chrysler went with the 13/16" to reduce the tendency of rear wheel lock up. The bulletin was geared toward the police car applications.
I have been using the 13/16" bore rear wheel cylinders on all my cars without problems.

 

[fullmetaljacket]

I think the pressure would be less. I have front disk brakes and there was a service bulletin about using smaller wheel cylinders on the rear drums. Smaller than the original 15/16" ones. Chrysler went with the 13/16" to reduce the tendency of rear wheel lock up. The bulletin was geared toward the police car applications.
I have been using the 13/16" bore rear wheel cylinders on all my cars without problems.

Interesting. So Chrysler actually made 13/16 units for Police services only or all across the board? I thought they were all 15/16 as far as the rears.
Are you going to construct a working model soon? I'm curious.

 

[Mopar John]

Yes sir. Iirc it went from 38 to 22. But it's getting close to 20 years ago now..
Took out some unnecessary gusseting as well

RemCharger,
Yours looks a bit skinny compared to mine!
It shows on the scale with me at -12LBS and your at -16LBS! CONGRATS!!
As I look at all these K-member pictures one has to wonder if there is a light weight manual box out there?
MJ

 

[fullmetaljacket]

RemCharger,
Yours looks a bit skinny compared to mine!
It shows on the scale with me at -12LBS and your at -16LBS! CONGRATS!!
As I look at all these K-member pictures one has to wonder if there is a light weight manual box out there?
MJ

What do you mean a lightweight manual box? The aluminum manual box found on all models is the lightweight version.

By the way, my manual box is mounted using titanium bolts, titanium adjusting lock nut and aluminum bolts for the top cover. that's as far as I've been able to go to make it lighter.

 

[Badvert65]

I put 13/16 rear wheel cylinders on my Belvedere years ago and have always had great brakes. I am now going to replace them with the aluminum version. I have a pair of the 13/16" aluminum cylinders installed already and just have to wait until I get the car's floor welded in and the engine back in.

 

[RemCharger]

RemCharger,
Yours looks a bit skinny compared to mine!
It shows on the scale with me at -12LBS and your at -16LBS! CONGRATS!!
As I look at all these K-member pictures one has to wonder if there is a light weight manual box out there?
MJ

Thanks! The last time I checked , the car was down to 3250. That's a 67 charger, all steel. Quite a bit of factory interior, full dash/ cluster, 5 pt bar

 

[fullmetaljacket]

I put 13/16 rear wheel cylinders on my Belvedere years ago and have always had great brakes. I am now going to replace them with the aluminum version. I have a pair of the 13/16" aluminum cylinders installed already and just have to wait until I get the car's floor welded in and the engine back in.
View attachment 1718039View attachment 1718042

What size are these brakes 10" or 11"?
Is the cylinder in this picture above aluminum? It sure does look like it.

 

[Badvert65]

What size are these brakes 10" or 11"?
Is the cylinder in this picture above aluminum? It sure does look like it.

Those are 10 x 2 1/2 factory brakes with the 13/16 aluminum cylinder I described.

 

[Mopar John]

What do you mean a lightweight manual box? The aluminum manual box found on all models is the lightweight version.

By the way, my manual box is mounted using titanium bolts, titanium adjusting lock nut and aluminum bolts for the top cover. that's as far as I've been able to go to make it lighter.

I wish I had a pile of manual gearboxes to weigh like I did on other small parts.
I do not believe that they are ALL the same.
There had to be revisions along the way and different suppliers.
What about the ones for the racing program or the Dodge Dart Lite's?
If any one has a loose one weigh it and report in.
If you have more than 1 see if there is a difference?
Thanks! MJ

 

[Badvert65]

My thinking is that there would be a difference in weight between the 16:1, 20:1, and 24:1 boxes due to the different internals. The cases have all looked the same to me so I wouldn't think that there was any difference there. I have a brand new 20:1 box and I think my other is a used 24:1. I will weigh them when I get a chance.

 

[RemCharger]

RemCharger,
Yours looks a bit skinny compared to mine!
It shows on the scale with me at -12LBS and your at -16LBS! CONGRATS!!
As I look at all these K-member pictures one has to wonder if there is a light weight manual box out there?
MJ

Being it's been 8 years since the BattleHorse was out of the stable I'll throw out an action pic

 

[fullmetaljacket]

I put 13/16 rear wheel cylinders on my Belvedere years ago and have always had great brakes. I am now going to replace them with the aluminum version. I have a pair of the 13/16" aluminum cylinders installed already and just have to wait until I get the car's floor welded in and the engine back in.
View attachment 1718039View attachment 1718042

That's what I thought. Gonna look further into this by purchasing one aluminum unit and studying what you have done.

 

[Badvert65]

That's what I thought. Gonna look further into this by purchasing one aluminum unit and studying what you have done.

If you prefer to keep the 15/16" cylinders, I will check my notes as I am fairly certain I have some prospects for that in aluminum.

 

[fullmetaljacket]

If you prefer to keep the 15/16" cylinders, I will check my notes as I am fairly certain I have some prospects for that in aluminum.

Please do. It seems you're on to this with all the research and development.

 

[fullmetaljacket]

Being it's been 8 years since the BattleHorse was out of the stable I'll throw out an action picView attachment 1718111

That Charger looks sweet and could probably be trimmed down, if not already to WO23 weight. There needs to be more of those making the rounds. The hideaway mug is so cool.

 

[fullmetaljacket]

Being it's been 8 years since the BattleHorse was out of the stable I'll throw out an action picView attachment 1718111

How quick and fast is that bad boy?