How can I do it? Is it necessary on a RST boosted 13 psi? What are the advantages of it?

Thanks...

 

i couldnt tell you how to do it but what it does is dump fuel into the mfi plenun which increases your fuel rate as you cant change injectors running mfi

 

You dont need it on 13 psi mate

 

13 psi will not need a fifth injector

in SA before local tuners reversed engineered the Ausie Microtech and built the Domingos(now Gotech) standalone system , we used a hop switch(adjustable pressure switch) wired to a microfueler with an injector plumbed into the intake

at a set pressure , the hop switch closes , activates the microfueler which pulses the injector. The microfuelers pulse duration is adjustable

arcane way of dumping fuel into your motor though

 

What other mods do you have, if the engine has all the correct bits it could max out the MFi at 13psi

 

5th Injector isn't a bad idea. Due to the primative adjustment of the MFi system, it will allow you to run sensible off/low boost fuelling and provide the increased fuel required for boost.

IMO, MFi can do 13psi, but the above applies.