<chuckle> Its a cheap way to make a screamer as I found out by accident
a few years ago...
I had 3 of the 4 bolts that hold the turbo onto the standard manifold just a
bit loose, everything was fine until it hit about 6psi then it screamed like
some mad kid that sat of a drawing pin, the amazing thing is, it was quite
repeatable and almost addictive
Some original photos have not been recovered yet.
the four which hold the turbo onto the manifold need to be vveerryy tight! mine came loose, and not onyl did i loose 2 of the 4 nuts but the vibrations absoloutly rooooted the turbo gasket! plus u loose boost.. just tighten them up.
Carlos