If you plan to install an adjustable FPR then an under hood fuel pressure gauge makes adjust it much easier. If you don't then an electric Fuel Pressure gauge is useful but the cost make it prohibitive. I had one in my Civic and personally an under hood gauge would have been better.
"The 300ZX Turbo is a dance; it's a song; it's rolling, roaring automotive art. There is no color that doesn't suit it. There is no mood-lifting chemical substance it can't replace." - Automobile Magazine
