sometimes i hear a noise coming from the engine when i accelerate above say 2.5RPM's....usually within 20minutes of starting the car.

It kinda sounds like a timing belt or the sound a car would make when doing a burnout......(screahing kinda noise), it goes if ease of the throttle).

not to sound stupid but i believe (correct me if im wrong) but the car has a metal chain and not a rubber timing belt.