I hear a grinding noise when the engine revs past 3k rpm. The noise almost sounds like metal grinding and when I let off the gas, it goes away.

The car was running fine before but noise came after I removed the airpump, installed Greddy pully kit, replaced all vacuum hoses and Koyo radiator.

Help?

 

Did you check the belt tension to make sure you didn't over tighten the belt?

 

how tight are the belts suppose to be? I didn't use a TQ wrench, just tightened it by hand.

 

You'll need to check the manual. They have the proper deflection listed in there. IIRC, it was around .5" or so but refer to the manual for the exact numbers.

 

ok, the noise is actually from a leaking BOV. I tightened it and it went away...thanks Mahjik.