watch out for the ls7. As chev made them they had a tendency to drop valves. They had bad exhaust valves and bad guides. Most of the vette guys ended up either lunching motors or paying to have them fixed as a preventive maintenance. Its a good motor if you address those problems though. The real bargins aren't those high dollar motors. You can swap a 300-350 hp crate motor in a pickup or older car for around 3 grand. Consider most of those old cars and trucks with 350 chevs were lucky to be putting out 200 hp its huge jump in power for not a lot of money. its to the point today when its about silly to rebuild a motor. By the time you buy parts and pay for the machine work your into as much money and you don't get a warrantee from yourself. GM performance sells complete engines with 3 year warrantees for starting at about 2 grand.