Originally Posted by whonickjones84
What does it sound like at 60%? Distorted as hell? Just because the knob will go higher doesn't mean you get more power from the unit.
By your description ("a Kenwood stereo"), I would assume an off the shelf, standard one piece combination receiver, CD player, and four channel amplifier. You are only using two of the channels. You have no more than 90 watts of power available (for two channels) and even that will be at a very high distortion.
If you just want more volume, the first thing you should do is install another pair of speakers connected to the other amplifier outputs.
I suspect that if you run the stereo at full power for very long, you will damage your "cheapo" speakers anyway.