ok i have the drum brakes on my 87 trans am. should i convert to disk? is it a difficult thing to do? brakes are just not my department

 

Yes. No. This is a frequently asked question. A will provide all, or nearly all, the info you require.

JamesC

 

What kind of driving do you do? If you just cruise and daily drive, then unless you get a good deal on a kit or require top of the line stuff you really don't need them. The rear of your car does what- 30% of the braking. drums are still adequate for that and are still being used in new vehicles today.

If you are into high performance driving and racing, etc then you should definitely consider them. As you know this type of driving builds up a lot of heat (braking hard at high speeds)- and that's the biggest problem with drums. they build up heat (they can't dissapate it fast enough) and then fade as a result. Once that happens you're in trouble.

When I switched my 1984 Trans Am over from a rear drum to a rear disc- this is what I faced:

rear axle for drum cars has a different mounting flange than the disc brake rear axle. (If I were to use factory parts then I needed another rear axle.) Meaning I couldn't just bolt up factory disc brakes on a drum axle.

Also need the rear calipers, rotors, brake lines, proportioning valve and master cylinder for the 4 wheel disc brake cars.

There's a different part # for the master cylinder for a drum equipped rear versus the disc equipped rear.

Now, if you use aftermarket brakes you probably won't need to change the axle housing as they'll likely design it to work with either style rear end.

Remember, drum brakes have a different requirement for fluid (volume/ pressure, etc) to operate than discs do. discs take more effort to operate than drums, which is why you don't see disc brake cars come without power boosters. (Drum brakes have a "mechanical advantage" in their function so they can operate without the brake booster- which is likely why there's different part #'s for the master cylinder for a disc or drum car...) This is why you need to switch everything over- so it'll operate your new brakes properly.

Discs are open so air gets to them and cools them off, helping reduce brake fade considerably. they're not all bottled up inside a big iron drum. Plus, the shape of the drum itself is a cantilever shape- so when the shoes are pressing against it- it's only being held on one side. Press hard and it can distort- reducing the effective contact area between the shoee and the drum (reducing your braking ability). And, discs are simpler in design. easier to work on, not so many springs to go flying all over the place, etc.

As mentioned- do a search, maybe buy a book and read up on it (brakes). Then you'll be full of info and know exactly what you need and why you need it.

I hope this helps. Good luck!

 

apparantly, I stand corrected on the drum/ disc flange on the rear axle. I saw another post/ link where a drum flange was modified to work with the discs. so it can be done with some work involved...

 

thanks for the info guys. ya its gonna be my street/strip car when the turbo 350 is done. so im lookin to see whats best for my plans