i have a d15b vtec jdm . the engine automatic cut off when it arrive to 7200 rbm. that mean if i install turbo i need no turbo boost controler or it is important to keeb my engine safe ?

Your going to need a boost controller if you want to run boost greater than what the wastegate is set at. If you have spring for 6psi then you could just directly route a vacuume line to the wastegate, but there would be no way to raise your boost. A boost controller can not let you have less boost than what the wastegate is set for. So all and all you do not have to have a boost controller as long as you are happy with what the wastegate is set at.
-Andrew