Yeah there is a tonne of really good info on the parent site. I was a bit blinded by the fact that I was looking for compressor maps when I found it so I didn't list any of the other stuff.
Anyone with an interest in the way engines work, especially the more theoretical side of it go and get reading at http://not2fast.wryday.com/. It's a good collection of really hard to find info.
And incase anyone was interested in the NACA reports he has copies of, NACA is what NASA used to be until they went into space. This will give you some idea of how old the reports are.
The bit on induction tuning is worth a read.
And check out some of the bizzare turbo manifolds he has photos of. Try the wastegate on this one