Rear drum brake upgrade

[richp85elco]

Just finished up my rear drum brake upgrade, since there aren't too many pics of the process i figured i'd share mine.

first replaced stock 3/4" bore wheel cylinders with S-10 7/8" bore. I also highly recommend using wheel cylinder bracket because the retainer is a pain in the *ss to get in and sometimes they are still loose. I couldn't get the new retainer in so i reused the old ones just to hold the wheel cylinders in place to install the brackets. You will need a 15/64" drill bit to install the brackets.

You then want to use two primary shoes per side, the one on the bottom is the shorter stock secondary shoe, it has about 1/2" less contact area then the primary.

And that is basically it, you gain more holding power which is good for launching and i would say more stopping power although this is highly debated lol you can also replace the rubber lines with stainless steel braided ones for better response, but I seem to have bad luck with brake lines so I didn't..

I also replaced the stock cast iron drums with aluminum drums to save weight and better heat dissipation + i love the look of aluminum.....especially when polished 8)

have cat litter all over my garage so everything is a little dusty

 

[pontiacgp]

That's nice upgrade and those polished drums sure do look nice with your wheels...

 

[richp85elco]

thanks! it looks much much better in person, but I have kat litter dust being kicked up all over the place from my shift kit install.

 

[crucial118]

So you have to by 2 sets of rear g-body brake shoes?

 

[pontiacgp]

So you have to by 2 sets of rear g-body brake shoes?

that's the only way.....

 

[crucial118]

Thanks PontiacGP. I didn't know that part of the upgrade. I thought it was just the wheel cylinder that was the upgrade.

 

[crucial118]

Good write-up, Richp85elco.

 

[pontiacgp]

Thanks PontiacGP. I didn't know that part of the upgrade. I thought it was just the wheel cylinder that was the upgrade.

I have read that some think there is a drawback using two primary shoes. The drum expands when it heats up and two primary shoes with more friction heats up the drum quicker which causes the brake pedal to travel further and affects your braking capacities. The larger piston in the non power bake is a great upgrade and the girdle holding the cylinder in place is really needed to keep the cylinder in place. When the cylinder moves you loose braking force on the shoes

 

[Longroof79]

Good write-up, man. I've wanted to eliminate those useless clips that hold the brake cylinders in place. What a poor design.
Your aluminum drums look great. Yours are the first set that I've ever seen polished. 8)

 

[dogsht]

I did the same upgrades to both the GN & 442. In the case of the GN it does help it hold the line better at the track and can be seen in before and after 60 foot times. Also I installed a proportioning valve. When I first did the larger wheel cylinders & both long soft pads on the GN if I would do a panic stop especially on wet pavement the back would lock up before and or without the front. If this happens you just adjust the proportioning valve and test until the problem goes away. All in all its a good easy and cost effective upgrade compared to converting to disks in the rear. Naturally disks would not fade as much under repeated hard use but they don't help hold the line any better so which is best depends on what you are using the car for.