so I was doing some testing on my car tonight and my normal fuel pressure of 40 psi was way to lean on the wideband (first time I checked this car with it). Even when I turned it up to 46-47 psi, the car was still at 14.0afr at 5500 rpm in second gear. my upgrades: Stock block and heads (91 Fox) GT40 Upper and Lower intake manifold BBK 65mm Throttle body BBK Throttle body/EGR spacer C&L Cast aluminum intake Pro-M 75mm MAF E303 Cam BBk Fuel pressure regulartor M.A.C. Shorty Headers Dynomax 2.5" H pipe and exhaust (dumps at angle just before rear axle) *has resonators before H on each exhaust tube MSD 6a and blaster Coil *Timing is set at 12* on 93 octane Could it be reading leaner than it actually is because I am getting my reading at the tail pipe? The fuel pressure gauge use to read 2psi less when I had it on the fuel rail at the Schrader valve location. The gauge now sits on the BBK regulator.