What is this? And do i need it?

[MELLO*SOS]

Originally Posted by MavericStephenc

I think that is for the stock boost control solenoid.(boost cut) but I'm not sure though

Looks like a Map sensor used by the ECU to control boost cut solenoid. RB25 has something almost identical. It's to limit the boost under certain situations, you don't really need it.

Do the timing yourself, just pick up a timing gun and download the FSM that the other guy showed you. There is a process to putting the ECU into timing/idle set mode, like on the KA you have to unhook the TPS, not sure what the process is on the SR (probably the same)... Check for boost leaks like was suggested.