Help!
 

Im buying 4" lift blocks for my 2002 chevy blazer 4 door ls. I believe my rims are 17". What size tires do i need for proper balance and so that my truck doesnt look weird with little tires and a large lift

What do you intend to do with lift blocks on your truck? Blocks will lower the rear and I suppose (not to sound like and ass) you could use the other two to chock the front tires while you lower the rear! Please do some research you need shackles or AAl to lift the rear and since if I remember correctly you have a 2wd you will need lift spindles for the front. Take some time and search around the forum and learn a little about your truck. I really don't want to sound rude but there is so much info on here and two minutes of reading would have told you that blocks will do nothing for you!

Yeah "lift" blocks for the rear ends of our suspension will lower the rear due to the fact the springs are under the differential.... unless you've done a SOA (spring over axle) mod already.

So i get shackles or aai, and larger springs for front? Im not really understand the tire situation what dimensions do i need? I have a friend who can i stall it i just bother him too much with my questions, as you can tell suspension and wheels arent my specialty. Lol

Ok dude... search in here for the things you want to do to your ride. As in, you want to lift it a bit but not spend much money: search for torsion bar twist or crank & search for shackles. Tires & what will fit have been covered in here & you can find lots of info by searching & not bothering your friend lol.
I think there's a DIY (Do It Yourself) thread on what tires will fit.

Btw what is an aai? Why do you believe your rims are 17"? 17" are aftermarket & if you're unsure - read the sidewall of the tire. It'll tell you all the dimensions of the tire including the rim size. As in stock for your vehicle is (I believe) 235/75/15, the 15 being the rim size.

^x2 please search its all been covered!!!!