actually a couple lol. after putting on the 2.85 the blower was a little louder on idle (kinda sounded like rocks or something in the blower) not TOO bad though, just a little louder than before.

however, sometimes now im getting an RPM dependent "howl" i think its coming from the blower, but im not sure. it happens under normal non-boost driving and stays in line with RPM. almost sounds like a pulley/belt slipping or something, but im not sure. anyone have any idea what im talking about?

I Also Have That Rock Noise. For Some Reason It Comes And Goes. Dont Here It All The Time

anyone? is it just because the blower is spinning faster all the time?

I found this thread man.
Some had the supercharger replaced and it came back but most say its normal.

http://www.cobaltss.net/forums/showthread.php?t=77921&highlight=rock+noise

my blower sounds like rocks are in it when it gets heat soaked

check the boost vac hoses that go to the gauge's sender unit. make sure there are no leaks.

If not, take the belt off and see if there is play with the pulley. If there is, its coupler replacement time.

the rocks noise doesnt bother me as much as the howl. i have no idea what it is, and it never did it before

the rocks noise doesnt bother me as much as the howl. i have no idea what it is, and it never did it before

well it will "start" to whine alot earlier due to the pulley drop. I thought i had a sort of howl until i cleaned my s2 belt off. I dont know without a vid.

The rocks sound is normal... its due to the roller bearings and the rotorshafts. The cobalt superchargers have no engine torsinoal vibration isolation device all of the enigne firing vibrations are transmitted throught the belt into the supercharger. Since there is no load on the supercharger during idle, the rear roller beargings allow the shafts to move around 'slightly' thus creating that sound. As soon as load is placed on the supercharger, that noise goes away.

its def. not the same noise. i know the blower whine, and this is not it. cleaning the belt might be a good idea. i think im going to do that and reinstall the pulley today. see if that helps. what did you clean the belt with.

also, it doesnt do it all the time, hell it will do it, then stop all in the same drive sometimes

its def. not the same noise. i know the blower whine, and this is not it. cleaning the belt might be a good idea. i think im going to do that and reinstall the pulley today. see if that helps. what did you clean the belt with.

also, it doesnt do it all the time, hell it will do it, then stop all in the same drive sometimes

black magic engine cleaner is the only thing i use.

It cleans all the oil off the belt after an oil change (some blows up the dipstick and on the belt) as well as conditions it like new so it doesnt crack or break. Just let it idle and spray both sides and let the rubber absorb it. If your belt is pretty dry rotted then u may need to reapply after an hour or so.

DO NOT use some sort of adhesive belt dressing. That will take MONTHS to get off.

cool ill do that and reinstall the pulley

the stage 2 screws were too long and rubbing the housing behind the hub. you guys heard of this before?