From the sounds of it, he probably replaced the original dead motor with another built one.

Stage 3 cams would most likely be 272 duration. Hes prob raised the idle so it doesnt hunt at idle or sound so lumpy.

Hey thanks nisssky for the link i think my motor is def a 3sge ... but i still dont know why he changed the engine number unless he bought the engine built and just used the engine number of that one ..yea its very lumpy still everytime i give it it feels like i just turned up the bass on high .. it would sound good with my after market exhaust but i think ill get the tuneing done and get the exhaust put on at the same time ..would love to see how many kw the car has after a dyno