The wheel flows about 64.8lbs/minute but because of the larger compressor housing AR and the larger 5" inlet it is not comparable to an s300.
From Mike a true turbo genius
"Also, remember that the S400 compressor covers all have larger volute dimensions (A/R) than any S300 cover, which isn’t something easily reflected in a compressor map.
Now, the 318407 compressor, well, that’s a turd, plain and simple.
It was designed for, and works well, on 330-370HP, 11.1l DDC Series 60 engines, but I have never intentionally applied it to anything else, as it’s a fairly old, non-ETT design. "