Could it be my fuel pressure regulator?

I drive a 1999 Honda Prelude and recently I found fuel in the vacuum line. So I replaced the fuel pressure regulator with a part bought from advanced auto parts and now I noticed a longer crank time under start up. Before, the engine would fire up within 2 seconds of cranking but now it takes a bit longer. I noticed that if I pressurize the fuel (engage the fuel pump) 5 times before starting, the cranking time is shortened! I was thinking to rent a pressure gauge to see what's going on but could it be that the part isn't genuine honda? I'm not seeing fuel pump symptoms but I'm also looking at replacing the fuel filter since its overdue but this is a problem that wasn't there before replacing the fuel pressure regulator.

A aftermarket fuel pressure regulator should work just fine.A oem regulator will usually last a lot longer than a aftermarket one will. I would replace the fuel filter and rent a fuel pressure test kit so you know exactly what's goin on. Most vehicles should have between 35-50psi of fuel pressure with the key on/engine off. Then start the vehicle and take another reading.Pressure should drop to 30-40psi while engines running. If the readings you get are below these numbers, the fuel pump may be defective. If you had to cycle the key on/off 5 times to buildup enough pressure to start the vehicle, that's usually a sign that the fuel pump isn't keeping up.Another thing that can cause hard starting(if its fuel related)is fuel injectors that are leaking down. You can test this scenerio by shutting the vehicle down and watching what residual fuel pressure does. If pressure begins dropping rapidly after shutdown, the injectors are leaking down.Another way to test is by checking the spark plugs.