Requesting Help on Tip Size

I am jumping into the cleaning business. Playing around with my own shop and fleet. My shop is hammered in oils and grime on the slab. I am looking at what chemical and application process y’all recommend? Also I am Running a 3000psi 4 gpm unit. Surface cleaner is a 20” 2 nozzle. The SC cleans decent but seems like it is not putting the water and pressure to the ground like it should. I exploded the unit and made sure there is no blockages in the SC. I am coming to think the tip size on my SC is wrong . Could some one here help me out and put me on the right tip size and any other tricks to make it run to its full potential?
Thank you for your time

^^^
Here is a link to a thread that covers tips and what not for SC’s. Read over it and it may answer your question and you’ll learn a little bit of knowledge in the process as well. There are a good amount of threads in tip sizes and what not; hop on the search function here and read away. You’ll be happy you did and so will your future clients.

To put 2500psi down you need 25025’s.