Alien OEM Fuel Pressure Regulator pulled from 03' M3
Changed the fuel pressure regulator today. I am perplexed because the one I pulled out of the car is a Bosch 3.5 bar not meant for the S54 engines (#0280160597). I've never noticed any ill effects; I am second owner, and picked up the car at 17k miles (Currently at 52k). I dyno'd it shortly after I got it with only a Borla muffler (Installed by previous owner), and it put down 278 rwhp on a mustang dyno after 3 runs in about 72F at 2600' elevation.
The FPR I just put in, is the correct 5.0 bar meant for the S54 (#13531404089). I've tried researching this, and it seems that the 3.5 bar FPR I pulled out never should have been on the car. I have all the maintenance records from previous owner, and of course the FPR (or anything fuel related) was ever touched.
Any explanation for this? I'm concerned running the new 5.0 bar FPR will induce some issues.