Hey just wondering if anyone is running a gt45 or similar on a standard motor? What rpm do you start seeing boost and what rpm you have full boost?
Stock motors or worked, just wondering

Also is a borg warner sc400 roughly the same size?

Guessing you mean an ebay gt45? Both the BW s400's and ebay gt45's come in heaps of different configs, and are available with anything from a 69mm compressor up to 80mm, a bunch of turbine sizes and all sorts of housing options. Heres a good list of s480's

http://forcedinductions.com/productsborgwarner.htm

You'll need to work the other way, what are your goals and budget then since up a turbo accordingly really. Not many people run BW sx's on XR6's, but a similar garrett would be a gt4294 which also has a 75mm compressor and people say they're making full boost by by 3200-3500rpm. Believe that turbo will do ~1000whp.