My CX's pump with 165k miles still ran fine. I don't think you'll see any gains unless your old pump is going south. A new fuel pump is wroth investing in, if nothing else, piece of mind (pumps only last so long).
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Andy - Reinstated
Hybrid Forum Moderator
'06 Subaru Legacy Spec B - Stock, for now
'98 Civic EX - CTR headlights and grill, Kosei K1's, for sale
'90 240SX - SR20DET that will never get installed, project car.