Hi all

A question for the mechanically aware guys among you i was thinking of getting an adjustable fuel pressure regulator and was wondering is it possible to adjust the air/fuel ratio on a rolling road if your car is running too rich or too lean by adjusting the FPR?

Car is a 1996 wrx import

steve

 

You Can change it to some degree, but is in no way a means to alter the fueling on a car that is not mapped correctly.

 

In essence, yes. However, as you might expect this alters the fuelling across the whole map, so say you've got a problem with it running lean at full load; if you give it a little extra fuel pressure to sort that out, you'll find it'll be too rich across all the other conditions.

So if you're mapping the ECU on a rolling road, yes you can tweak the fuel pressure to get your injector duties correct, but the actual nitty gritty of AFR throughout the map needs to be programmed, not adjusted with the turn of a screw...