srry for the noobish question, so when an amp says 600 watt 4-channel amplifier it mean it can run 2 300 watt subs?
Yes you can.
The 600W is the maxium output, so 300W+ 300W = 600W. You can have bigger subs if you want but the AMP would not be able to use the full potential of the Subs.
4 channel means that you can run 4 sub individually. You could also use a single channel and still use one or more subs, but all the subs would sound the same because they are all getting the same signal. If you use a 4 channel, this means that the sound will come out differently for each speaker based on how you set them up. You coud have a signal be the Front Left, Front Right, Back Left, Back Right.
*it is kinda tough to explain, but I hope you get the idea.
any amp can run any sub…just the more closer you are to the reccomended power the better it sounds (you don’t want 5 watts running a sub 
)
Its all about RMS power, anything else is hogwash and is just printed on the amp so it “looks powerful” Read the full specs on the amp… I would suspect a 600 watt 4 channel would be a bit lacking but then again I don’t know the specs… Match the RMS power of the sub to the RMS power of the amp (or as close as you can) Overpowering will not hurt your subs, as long as you arent “clearly” overdriving them when listening to them…under powering wont hurt either but you do risk distorting your amp (and distortion fries speakers…regardless of how powerfull the amp is…a 50 watt amp can melt down a 2,000 watt sub if driven hard enough) As long as the sound is clean and not overdriven or distorted, it will play forever…
as for your original question…it depends on the subs and the amp…The subs could be dual voice coil or low impedance (ohms)…but in general you can bridge the channels on a 4 channel amp, to create 2 more powerful channels. Those channels SHOULD be able to drive subs at 4 ohms. But if the subs fall below that (depending on the type of sub and how their wired) you can cause the amp to go into “protect mode” Post the specs of the subs, and the amp and ill set you up with a wiring diagram to make sure it will work for you…
ZX2ER explained it better than I but felt the need to further explain it.
I would suspect a 600 watt 4 channel would be a bit lacking...
...in general you can bridge the channels on a 4 channel amp, to create 2 more powerful channels.
That is because most AMP are setup to split the Wattage by channel. This is why you see on your 600W AMP will say 4x150. That is 4 channels, each putting out 150W a peice. When you bridge them as ZX2ER stated, you increase the power output per channel because you will take 4 channels and create 2 channels (150W + 150W = 300W).
ZX2ER is also right about RMS (Real Music Sound). RMS rating is generally lower than Wattage rating. It is very rare that you find an AMP with the same or close to RMS as Maximum Wattage.
a good rule of thumb is that RMS is generaly about half of what Maximum wattage is.
Dang you guys went the extra mile to explain all this for me, its getting very clear for me now thanks guys
im just curious on how many watts the stock amp is and i cant seem to find it, is it like under the carpet or something. Do i have to take out my front seat to reach it?
and wat would happen if i tried to run an 800 watt sub on the stock amp 
not a whole heck of alot, the cone might move. I believe only those who had the upgraded radio package got the amp. The stock amp wouldn’t push more then 50 or 60 watts because it was made for speakers not woofers.
The amp is for those with Premium Sound. Like Mark said…not very powerful. Especially not for a woofer…unless maybe it were only a 5".
- Darron
so those without premium sound dont even have an amp, so out speakers run off what? 
srry for all the questions im just a dumb 16 year old :roll:
Well the radio itself is an AMP, just not a very powerful one. Enough to run the 4 speakers that came with the car.
ok thanks thats all i need i hope they dont charge so much for stereo intstallation