It depends on the A/R ratings for the spool time. I have a pretty small T3/T04B turbo, my A/R ratings are .48 on both turbo housing and compressor housing. Most T3/T4's are .64 A/R ratings There so many T3's and T3/T4's its amazing. if you want a faster spooling turbo then get a A/R rating thats at about .48. My turbo spools at about 3800-4100rpms. My redline is at 6000rpm, my cars very driveable yet makes great power.