The Stovebolt Site Forums The Shop Area Engine Shop cruzin' at 70

Stock brakes in good condition will stop you just fine from 70 if they are just used for that once and then let cool for at least 2 miles. They will not work well for stop and go traffic. They fade quickly after two stops from 70 mph. Using a semimetalic lining will help but will shorten lining and drum life. I suggest you stop hard numerous times from 60 mph on a lonely road so you get a feel for how the brakes fade. You should notice that it is harder to stop but you will still be able to. Once they fade (they will start smoking too) pull over and let them cool off by parking with the engine off in gear but without setting the parking brake and let you foot off the brake. That will keep the drums from warping.
I check my car and truck's fade resistance every time I do any brake work and about every 20k miles just as a precaution. I own a sports car and drive on the twisty back roads a lot and it really sucks when your brakes fade and you should know what it is like. The idea is to know the limitations of your brakes and either drive below them or upgrade them.
(edited for lysdexia)