fuel rail?

[Unit 5302]

Aftermarket fuel rails need to be used in very high horsepower applications because their larger I.D. allows for greater fuel flow. There is some dissent as to where the stock rails no longer provide enough fuel flow in terms of horsepower (this is especially so because so few cars actually need them), but I don't think you should start even comtemplating them until you're at or above 500hp or so. Unless you want them for looks, that is.