I have pq 270 laser 502 stock single engine don't know what to use for a prop 3 year of owning boat??

without knowing anymore about your setup, I would say a 25P Mirage plus is good to start. Or a 24P Bravo1
What do you have now?

crusing rpm's is about 4300 will go to about 5300

What is your speed at 5300 rpm's, you can go to a prop calculator and see how much slip you are getting with the 3 blade

My 280 silencer with a HP 500 efi came with a B1 24 pitch four blade. Worked well. Cruising speed with a three blade sucks.I'm assuming you have around 415 - 430 hp ?

Hello,
We have a test propeller program if you are interested, please call us and we'll do our best to help.

Brett

5300 rpm's it says 58 mph on gps may be thats good for that boat. 502 efi motor thats got about 700 hours on it still runs strong. Just new to boating some what just wondering thanks for the help..