fuel pump??

[sho_evo_209]

Does anyone know when our stock fuel pump maxis out??..... because i am miss fireing on top end. I reaplaced the spark plugs and put in some densos. my mechanic said that it is because my fuel pump is already maxed out and cant push anymore fuel then it is now and i am boosting anywhere between 24-27 psi!!

[Warrtalon]

1) There is no exact point, but you shouldn't be using the stock fuel pump anyway if you're running more than stock boost. Upgrading the fuel pump is a STAGE 1 mod on VIIIs. Running 24-27psi on the stock fuel pump is simply absurd...

2) Denso plugs are a bad idea. Should be using NGK BPR7ES gapped to .026 or BPR8ES gapped to .024 if you're running that much boost. You should know if it's 24 or 27...shouldn't be saying "anywhere between 24-27." Get your boost set where it should be for the octane you're using and where you're tuned. Boost is not a game.

[Evolvd]

Or the simple short answer would be yes, you're fuel pump is maxed out for the boost you are running. Easy fix.