Originally Posted by S65B40V8
OK, how about this: any chance it's the intake resonance sound? This engine has a very distinct intake resonance in the 3-4k RPM range at say 70-100% throttle. I would describe it almost as a tearing cloth sound but could also be described as a knocking sound. BTW, I love that sound -- to bad it is only heard in a narrow RPM band.
No, it has been discussed before and it def resembles a typical engine knock. The intake noise is something diff.