My car is bone stock and has no ***** down low. Ive been getting horrible gas mileage and everything on the car emissions wise, has been replaced within the past year since I bought it. So I tested my fuel pressure again. Unplugged the thing and started it it up and bam 52psi. That seems a bit high right. Like the cylinders are getting drowned in fuel at a launch (where my car has no *****, im talking no chirping of tires) and bad highway fuel economy.

What is the best AFPR? Crane? I heard the Holley ones are problematic with the diaphragms going out routinely. I was thinking of buying a new GM unit and making the bad one I have an adjustable.

But my main concern, is my FPR bad?

Actually that sounds a bit low. It's 43 psi relative to manifold pressure. So add 43 to atmospheric pressure (since you unplugged it from the manifold) which is 14.5 and you're at 57-58 psi.

That is unless I've gross misinterpreted what regulator pressures are supposed to mean and someone else will come in and bitch slap me.

Vacuum line unplugged you should be at ~43 PSI. With vacuum line attached you should see readings down in the mid 30s, variable with engine vacuum, of course.

Might be an issue with the FPR but also check for restrictions in the return line (kinked line, etc.).