How much power can an LQ4/9 block and crank handle? I've heard anywhere from 900-1300, but it always varies.

Any proven motors making that power with a stock block and crank?

 

stock crank should support 800-900hp, but if you are running that much hp, why risk it when you can buy a forged crank that will support more than you'll ever make for just a little chump change?

 

I've also been wondering what the block would hold.

 

By the time you're exceeding the HP capability of the LQ9 block or crank, you're spending so much money as to make the question irrelevent.

 

stock crank+6.0L iron block= 900rwhp+ Many have gone over that number, and many more have lived in that range or close to it for a long time without issues. Just get quality forged pistons/rods and rod bolts and get a gangsterrr tune. Should be fine