Ok, i have a GSR, im putting a turbo kit on it, i have 440cc rc injectors and walboro fuel pump,

I bought a missing link, Can i use the missing link INSTEAD of getting a Gm 3 bar map sensor? my understanding is that the missing link tricks the ECU into thinking theres no boost, as a gm 3 bar reads the boost and controls the ecu to handle it?

 

You'd want to have it tuned to properly handle the boost, so obviously the missing link is a bad idea.

 

A missing link is used for a stock ecu, since if goes into LIMP mode (3.5k redline) if it reads over 1psi of boost. The missing link is a fancy check valve.

The 3bar lets your ecu read over 11psi. It must be chipped with an ems like Crome/S300/etc for it to not go into LIMP mode over 1psi.

I really would hope you don't post again until you've read through the forced induction FAQ on top of this forum. You have a motor that's worth more than a few bills, and its VERY easy to destroy it if you slap a turbo kit w/o a proper tune.