2011 GTI - a little more bass
 

I would like to replace the four 6.5" drivers in the doors. I am looking for just a little more bass, nothing crazy. All four doors have components. Is it possible to only replace the drivers and not the tweeters?

Yes it's possible. Whether you'll get more bass or not is debatable.

For the cost, I would look at a low profile box with a 10 and small amp..

Thanks for the reply!
Can i buy a pair of drivers without tweeters? Seems that they are all sold as component sets?
I am not interested in running a power wire and rca in this car. I have a complete build on my summer car :)

Most car audio aftermarket speakers needs to be amped and have a proper install to get more bass and quality over stock.

You can use pro-audio drivers which sells as separates, but again you may need to amp them or do a good install to acheive what you desire.

This is what I will be installing up front...
Focal IFVW Golf 6 Custom-fit speaker system for 2010-up Volkswagen Golf/GTI at Crutchfield.com

If I swap out the woofers at the back, how would I acheive a clean connection with the stock connector? Will it be a simple plug and play?

You will have to cut the connector and crimp on or solder on spades. You will also have to drill out the rivets holding the stock speakers in.

Drilling out the rivets is ok, chopping off the stock connector bothers me!

It can always be reconnected. You might be able to find an adaptor harness but I see that as an added unnecessary cost.

Why are you taking so much risk you don't have enough knowledge about it so do not do by yourself call an expert and save your time.