3 of them were originally hooked up to the acv and i believe the 4th line ran to the fpr originally. i capped all of them and i just wanted to make sure this wouldn't cause any major issues.

thanks

 

The one for the FPR will cause you to run lean under boost.

This is how the FPR works, i am just making up numbers for fuel pressure and boost/

FP 35psi Intake Pressure 0psi Add 5psi of boost
FP 40psi Intake Pressure 5psi

The boost pressure will help push down on the FPR to keep the fuel flow the same

Without the vacuum/boost line you will get this

FP35 Intake Pressure 5psi----- So you are not getting all the fuel into the motor because the boost pressure makes the fuel harder to get in.