I saw a parts posting here for aluminum rear drums. Are they worthwhile for weight savings? I would assume they are iron lined (?). What are they off of?

I dont think that they are really for weight saving. I'm pretty sure that the are for faster cooling (less brake fade). I believe that quite a few pontiacs came with them, all that I have ever seen are the finned design. Ryan

There was some information posted on Team Chevelle about a month ago on this. A number of guys indicated what cars they came equipped on stock, so you could easily find them in the bone yards. My 86 Pontiac Parisienne (Glorified Bonneville) came with them.

They would have to be made of aluminum for weight reasons, not better heat distribution. Steel/iron transfers heat to air better than does aluminum, so aluminum drums will offer no heat dissipation advantage.

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Justin
-1967 Camaro SS350

www-student.furman.edu/users/j/jtrauner

Aluminum transfers heat at a fast rate than steel/iron. At 100 degrees kelvin, the heat conductivity of Aluminum is 3.0 watts/cm degree kelvin, while iron is only 1.32, less than half the heat transfer of iron. That's why its used as heat sinks in electronic applications. I believe aluminum drums were used for both reasons - to cool more quickly and save weight.

Howard, you are right. I was thinking about aluminum compared to copper. I stand corrected.

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Justin
-1967 Camaro SS350

www-student.furman.edu/users/j/jtrauner

I'd love a set for less rotating weight.

69er

So does anyone know of a "bolt on" application that we can scrounge from the junk yard?

RickD,

Go over to Team Chevelle and search like was mentioned earlier. They have a list over there I think. Mid-sized later '70's and '80's cars mostly.

I thought that I copied the list and stored it someplace but can't find it!!

One post that I did find in my stash was one about BIG aluminum 11" drums (I think) off a '70 Buick GS or Riv. Now that would make a great rear drum conversion if it is so!! pdq67

Weight watchers: 1978-and-later Malibu (and other GM A-bodies) used a rear drum backing plate that only weighed 1 1/2lb. each. The aluminum drum with a steel liner only weighs 9 1/4 lbs.. The normal steel setup with all steel weighs in at 22 1/2 lbs each.

69er

I read the Team Chevelle posts. Can these drums be purchased new from GM? Is there a part number?

Here's a list of aluminum drums I cut and pasted from the Team Chevelle site.

Some late 78+ G-body cars (Monte Carlo, Malibu, Cutlass, Regal) and some of the 84+
Camaros and Firebirds had the small 9" rear drums that were made out of aluminum.