Fuel press. settings on type S are between 41# to 49# adj. should be made on outside temps. at 40 degress or lower you can set it at 49# at 75degress or higher you can go down to 41# but you should have a fuel ratio guage to set for outside temp.

 

Hrmmm, lets see, what are the short and long term fuel trim settings at right now?? Probably 0% on the short term since any adjustments would have been trimmed out in the LTFT allowing the STFT to go back to near 0%.

But if the the car is near the base 42 (w/o vacuum) then all should be near 0%.

Point being, the car and PCM is designed to correct for the fuel pump slowing, injectors cloging or sticking, unmetered vacuum leaks, etc. This is the very thing that adjusting the base fuel pressure on a 1:1 FPR that the PCM will trim out within minutes.

If you are not running near 0% on both LT and ST FT then an FPR can help. Because IMO, the car runs best at the factory tables without an offset.