Quote Originally Posted by dumpdaccord
i have a z6....where the factory header seperates theres two round gaskets, one has a gap in it about 1/4 inch....

i her the knoock coming from the bottom/front of the block(only knocks between 500-2500k rpm...then goes away....

no change in performance although i have no power after 4900k rpm...just makes noise....still gets 30mpg

....knock or gasket....im gonna change the gasket but wonderin opinions...


also if its a knock will just new bearings fix the problem or should just grb another motor....


I had the same problem with a LS motor and the problem was my timing was off by like a tooth or two. it did the same thing, it had a knocking sound on low rpms and it did not have no power... i would be flooring it and i would be redlining it but it was really slow.