340 block or 360 block

One thing a lot of people don't know is that a stock 360 has more torque off the line than a stock 340 but the 340 will outrun the 360 as it revs much higher and breathes better. A 360 can be built to out perform it though.
When it comes to money, $5,000 on a 360 will get you more than $5,000 on a 340 for the simple reason that the price of the parts for each is different just because the 340 has a powerful history.