exhaust leak??

[ghetto5oh]

whats up guys, ive had an annoying exhaust leak for a few weeks now and yesterday when i finally had time to check it out i found a small crack below the headers, i think it might be on the block but is it possible to still be running with a cracked block for so long? What's the biggest block i can run using the stock parts off my current 302? thanks in advance

 

[Titan2175]

Ive got a 306 in my car that used most of the parts off a 302, up the compression and go to a 306 and you'll be golden

 

[ghetto5oh]

so pretty much just get a used block from the junk yard and make it a 306 to make my life simple?

 

[ghetto5oh]

whats a good price on a 302 block?