I didn't hit the end of the [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]X40[/words] but I was over 9" pumped. That was fully pumped to what was probably an unhealthy level. I don't actually train at that pressure, I usually pump to about 85% of my nbpel and hold that for a long period of time as it seems to work far better for girth.
Remember it's not about how far you are stretching, it's about consistent tension that you can sustain. You can probably back off a lot to get to around 800 grams of pressure. With the base screws loosened I can stretch to about 9.75" if I wanted to, but I don't because it wouldn't be healthy or bring gains based on my experience.