I have a 1997 chevy blazer 4wd. I was just wondering if it could be raised up in the front using the factory torission keys on the torission bars? If so how hi, just wanting 2 inches. and what would be the best way to raise the rear? longer shackles? and do I need to replace the shocks to only go up 2 inches?

 

Yes, you can raise the front with the original torsion bars and keys:https://blazerforum.com/forum/tech-articles-diy-29/how-t-bar-crank-37078/
As for the rear, shackles would be your best bet. I bought a pair at autozone for 20 or 30 bucks and they've worked great for me.

 

what about using the factory shocks? If I go up 2 inches

 

Have you even tried the search feature on this site? What you have asked has been covered many, many, many, many....many times.