This is probably the wrong section, but I am new here

I am an avid electronics enthusiast with a 2001 s40. I purchased the full wiring diagram off volvotechnicalinfo.com... Reading through it it looks like it has 2 boost pressure sensors for the ECU running at 5v logic. Has anyone heard of anyone using one of these sensors for a boost gauge? Or at the very least, does anyone know how accurate the signal is? If anyone is curious, I will probably try a LM3914 to provide an LED bar graph like this guy did: http://www.audiworld.com/tech/elec42.shtml I would appreciate any ideas! Thanks, jSd