I don't have any experience with it but from the research I did on building a 6.7CR would lead me to believe it would spool very well. I don't think it's too big at all. Some would say it's too small cause they like to just go straight to s464-67.7. just make sure you get the right turbine wheel and housing. I would think you'd want to only go either .91 or 1.00 T4