if u run higher boost will the turbo spool slower than runnin lower boost or the other way around ,or this doesn't affect spool-up???

 

the top boost level is set by the wastgate, it is closed when the turbo starts to spool. the turbo does not know when the gate will open .It spools as exhaust is pushed through. the spool up to say 10 lbs is the same if boost is set at 12 or 20 lbs. The strain on the motor has alot to do with spool up time. more strain more exhaust pressure ,quicker spoolup

 

It won't spool slower but it will take longer to reach your target boost, which I think is what you are asking.