I have been trying to dial in my expresso shots. Before swapping the shower screen of my Gaggia Classic Pro, I was getting a ratio of 1:2 with my 18g basket in about 15 seconds. However, after swapping the shower screen to an IMS precision Nanotech shower screen, I was getting the same ratio in 25 seconds. This is with consideration that the same beans, grind size, tamp and workflow did not change.
Is it normal for the shower screen to have such a large influence on the expresso brew?
Thanks in advance.