The VDOs are bloody expensive though. Hopefully you get the correct one - the problem is that a lot of sites just list the one pump as a generic replacement without mentioning the pressure. I'm not really sure what the impact would be of running a 3 bar pump on a 2.9, as long as you had a matching FPR - but it might throw out the ECU map as it would have been tuned to 4 bar pressure.