What are some simple reasons an LS1 engine would be sluggish and slow?

Question

We just bought a 1998 Firebird WS6. The dealership had it detailed, and the detail shop ran it out of gas, ruining the fuel pump. The fuel pump was replaced, but when we raced the car against our 3.8L Grand Prix, the GP smoked it...bad. So we bought the car for speed, and it's super slow. OBD2 codes show bad O2 sensors, but I know O2 sensors don't really affect the speed and performance. We know the tranny is in good shape, and the exhaust has just been replaced, aftermarket, from headers back, so I know it's not an issue with the exhaust. The dealer said they tested the fuel delivery, and it was within normal limits. What else could be causing the car to be so slow?

Answer 1

just take it to a good mechanic that has a engine machine that he can put it on and check it all out, probably just needs a good tune-up and the 02 sensors, and yes the 02 sensors regulate the fuel and air going to the engine.

Answer 2

the o2 sensors can def. affect the a/f ratio and subsequently affect performance...you might be too rich or lean...replace them.

you have to check everything...fuel pressure, ignition, cats may be clogged, general tune including fuel filter...

start simple

good luck