New belt but MUCH Noise!

[sublinux]

Hey i got a Cavalier 98 LS Automatic (Without A/C). I just replaced my serpentine belt because the old one was damaged. I bought a new one in a Canadian Tire for 30$ (On the box the name of the Cie is Torque). So i installed it start the engine all was fine. But when the engine start to be hot (Like 70-80 Celcius) the belt make a very BIG NOISE and then the light start to loose power. At idle i got a small noise from the belt.. but when i accelerate *2000 rpm* its terrible.. But at 2600 2700 RPM Bang no more noise! So is it the belt is too long or the belt tensioner is too old?

[bratt]

is your belt tensioner working properly? or does it not work? that can do it

[sublinux]

Update.. the belt tensioner is good .. the new belt was too long so i put the old one... Where can i buy the same belt?