More than likely it needs spark plugs and new ignition wires.
under the hood
Change the throttle position sensor, that will fix ya right up.
Right under the throttle cover.
Under heavy acceleration the transmission will not quickly downshift.
The thermostat for a 1999 Chevy Camaro V6 engine can be found under the hood. It is in the right side of the engine, under the throttle sensor.
On the passenger side of the throttle body under the air intake
either bad gasket under throttle body or bad iac valve
on left side motor under throttle body look at top rad hose
Follow the air intake hose to the throttle body. Mounted to the "front" of the throttle body are two sensors. The upper is the idle air control valve. Under this one...and a little difficult to get to is the TPS.
What vehicle? (It is possible that if the transmission is conventionally controlled that there is a cable that connects throttle body to tranny and aids tranny to downshift under heavy acceleration.)
Going from 0 to 60 mainly involves the throttle, engine, differential, and tires of a car. How fast it takes depends on the features
Why I can't tell you, but I'd suggest you clean the throttle body (don't let anyone tell you you can't do that on this car) and then reset the base idle following the correct SP. This is likely to help.