We　studied　the　gain　of　Raman-assisted　fiber　optical　parametric　amplifiers　(RA-FOPAs)　both　theoretically　and　experimentally.　We　investigated　the　relationship　between　the　overall　gain　and　different　combinations　of　Raman　and　parametric　pump　powers　using　contour　maps.　We　derived　a　normalized　phase-matched　model　to　determine　the　general　behavior　the　peak　gains　of　RA-FOPAs　operating　in　the　small　signal　region.　The　contour　maps　of　the　combined　gain　enhancement　can　be　used　to　optimize　both　indirect　and　direct　Raman　gain　of　the　signal/idler　in　RA-FOPAs.　We　showed　that,　in　a　given　fiber,　it　is　possible　to　optimize　the　Raman　and　parametric　pump　powers　in　RA-FOPAs　for　high　gain　and　high　efficiency.