Hey guys ive decided to ditch my 305 tbi and build up a mild 350 i was just wondering if this looked like a decent long block to start out with
http://philadelphia.craigslist.org/pts/765189490.html

 

It would be easier for you if they knew if it has been bored over, or any machine work done. It may be a good deal, but you also have to consider that $700 for a new block may save you money if you don't plan to reuse the heads. After machining, that used block will be a lot more than $100. Heads will offset some of that cost unless you want performace heads. If you want something close to stock, there are some very good crate motors with a good warrenty too. Options abound, just a matter of choosing what is right for you.