sr boost pressure sensor and wastegate valve

im puttin in a redtop sr20det and i dont have the boost pressure sensor or the wastegate valve control solenoid valve. can you guys tell me what these 2 things do, how nessasary they are and if i do need them where i can order these 2 parts.

I have been running my SR for six months with no wastegate soliniod valve. Just run the line from the turbo outlet directly to the wastegate, I get 7 pounds. The red top doesnt have a boost pressure sensor.

but is it alright to not have the wastegate solinoid valve then? not that i dont trust what u say i just feel more safe about having second opinions

it helps the turbo last longer. but yes it is ok to run without the wastegate.