bought car with a aftermarket FRP on it.. and its running rich.. i can tell by the plugs and smells real bad.. how do i adjust it.. looks like its this one from B&M

 

You need some sort of guage, so you can see how much pressure the fuel system is pushing. A stock LS should run somewhere from 36-42 psi. I'm running right around 40 with my B&M FPR when the vacuum line is disconnected.

 

alright, but how do i adjust it?

 

if it is a B&M, on the top, where the vacuum line connects, that is actually an adjusting screw. You turn it clockwise to turn up the fuel, and counter-clockwise to turn down the pressure.

 

alright thanks =D