I heard 4000CFM from a cummins engineer, somewhere around 280lbs/min. I think they are a 5.25" inducer.
Definitely takes somes cubes and/RPMs to spool that big SOB
they can range from 5 or so inches up to 8 i think on inducer. I pulled a few of the Qsk 50's (V16 cummins) they weigh around 350 lbs.
I think that most of the tractors you see them one are the light super stock alky burners, so I believe that put them at a 505CID limit. As for rpms I wouldnt even venture a guess.