I hve put in an aftermarket deck and new speakers in the front and back. Nothing special. I am wandering if i might need a bigger alternator. PLEASE help me out i am looking to put a small sub in the future???

 

If you just did a deck and speakers you definitely should not need a new alternator. You would need to add some big amps to your sound system to need an alternator. If it is cutting out I would say you have a loose wire somewhere.

 

Does the deck show "protect"?

If so, that probably means that a wire or your speaker terminals are grounding out.

Take a multimeter and set it to continuity. Pull your deck and locate your speaker wires. Place one lead to chassis ground, place the other to the speaker wire (one side at a time). If any continuity is shown to ground, you have found your problem. Check that speaker and possibly replace that length of speaker wire. 90% of the time it's a bad/shorted wire in these older cars.