Has anyone compared fuel pressure regulators back to back and seen any difference in AFR vs RPM at WOT or horsepower?

I am trying to understand if the fuel pressure vs vacuum curves for different regulators are different and if so, how different.

 

Bump

 

At WOT where the manifold pressure is roughly the same as atmospheric the 'curve' is irrelevant and they are all operating at base pressure. 3bar/43.5psi for most B/D/H/F series engines save for Integra (and likely Civic) Type R having a 3.5bar FPR. So no, there shouldn't be any difference at wot unless one of your test regulators is not working correctly or is out of an R.

Vacuum referenced FPRs don't increase pressure at WOT, they remove pressure at part load to maintain the same effective pressure when manifold pressure is less than atmospheric.

Read here: http://injectordynamics.com/articles...ure-explained/
and here: https://cobbtuning.atlassian.net/wik...hy+You+Need+It