My Nova story

okay so i got a 75 nova bout 3.5 years ago, it had a 250 i6, needless to say it was lacking in power. I recently bought a new chevy 350 H.O. crate engine. I had someone put it in. I have quite a few questions. the specs on the engine say that its dynoed at 330 hp and 380 tq, but that is the engine by itself. they also used a 131/44-inch header to get those numbers. I have exhaust manifold, and a th350 auto trans. 3.08 Limited slip. I was wandering if anyone has any idea how much actual horsepower/torque

my problem is that i get 11 seconds 0-60! i need to find out why and how to fix this

Jsut a couple of thoughts. Your exhaust is too restricted. Timing issues? Wrong carb or jets in the carb you have, ignition issues (Distributor) Could be alot of different things.....