Well, Im not very familiar with car stereo systems, but I think it all depends on what components you install.
You should post a question like this in the Audio and Electronics sub-forum. The guys in there will be able to answer your questions.I'd suggest starting a thread with a title like "92' 4Runner aftermarket stereo options" or something along those lines and then ask what kind of components you will need to install a powerfull stereo.
Im sure it'll be something like Optima YellowTop battery, high wattage amplifier(s) a capacitor to store power for your high wattage amp, all sorts of expensive wiring and then of course your headunit, new speakers, tweeters possibly built in?, and ofcourse sub woofers.
Thats just what I think based on my past experience and reading random posts on the subject. Try the other sub-forum for a good answer.