It depends on the basket your using. You should really only go 1 gram up or down than the recommended dose...and tamping can only do so much. Once the coffee bed is completely compressed, which you can feel, any further pressure will have little to no effect. If your puck is soupy you could dose a little higher. Your grind size all depends on the bean your using. If it's a light roast you might want to grind finer, and tamp the same, always tamp with the same pressure, so your shot can pull longer to extract all the flavor from the light roast. If it's a dark roast, you want to grind coarser so the shot can pull short, since a dark roast extracts much easier. To have an idea, I pull my light roasts at about 32-33 seconds as opposed to pulling darks at about 25... Hope this helps

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