Is it bad to turn up my bass all the way?

No! you should never turn up an amp more the half way with the gain or boost this will kill your amp you are now putting more power into your amp then you need to, Your amp life will be minimum, This is why they make more powerful amps!

Remember it is a amp! most amps are set to be used at half gain in this way the amp will get louder at a normal regression as you turn up your music

And also they will tell you that 2ohms is good yes it does double your power but it will inturn give you loss of amp life!

No matter what 4ohms sytem will work a life time of your car if you need more power you always buy a more powerful amp

You can turn them as loud as you want, but the louder they are, the shorter time i would use them at that level. Subs all the way up will most likely overheat at 30-45 minutes of continuous music. You dont want them overheating frequently, youll even notice that they arent as loud which means you need to just turn them off and let them cool.

You should be good playing them anywhere from 50%-75% power. And 100% only for the few songs you choose.

turn your radio up to the level you normally play it. Than from there set your amplifier settings. Don't turn it all the way up because it might send a distorted signal, clip or overheat. Also break in the subs. Don't blast them right out of the box. Play them at low volume for a week or two.

well i always kinda figured that if the volume control goes up that high then why not play it that high? I learned that after bowing my speakers in my room that its not the case... I wouldnt go all the way up there if I was you. You probally spent alot of money putting that system in. Itd be a same to wreck it.

Play it safe. Happy rocking!

a good tip is to wind your windows up.. it sounds louder and the plus side is we dont get to hear the mindless thud