[Chiketkd]

Originally Posted by longassname

No the ECU does not monitor fuel pressure. With the faster fuel pump your fuel pressure is raised accross the board increasing fuel delivery accross the board so that your afr is richer accross the board. At idle and cruise the ecu uses the oxygen sensors to move the afr back to stoichiometric for efficiency. The fuel pressure regulator maintains fuel pressure in relation to manifold pressure. When there is vacuum the fuel pressure is decreased and thus fuel delivery is decreased. As forced induction creates positive manifold pressure fuel pressure increases and thus the amount of fuel delivered increases. This is all mechanical not ecu controlled.

In regards to the above statement Michael, how well would the Stage 2v3 chip work with an OBDI SVX that has an Impreza fpr installed (fuel pressure raised to 43.5psi, instead of the stock 36psi)?

-Chike