how to perform a fuel pressure test on a tuned port engine? i have 87 Trans Am pretty sure 350 but maybe 305 was told 350

rear of pass side fuel rail, theres a schrader valve for you to hook up a FP gauge.

Look on your SPI sticker (glove box, white sticker w/ lots of 3 alphanumeric codes). Look for "L98" --> 5.7, or "LB9" --> 5.0

Different pressures, do a search for the correct pressure for your engine, then hook up the gauge and turn on (but dont start) engine. Check gauge.

i found the schrader valve, the cap was pretty hard to get off looked like it was corroded on there and found some white powder inside when i finally got it off. anyway i hooked up my gauge and it was tight on there. once i turned car to on, i heard pump prime but no pressure registered on gauge (did it like 5 times). i then turned the engine over and car fired up, still no pressure on gauge. now if the gauge was accurate and i had 0 pressure the car would not run at all right? it just read 0 needle never even flinched. it was a loan-a-tool from AZ so it probably was bad gauge