I'm unfamiliar with The Snail pump, but can help w/TheVV. Others have used different methods, but this is how I modded both my [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]X40[/words] and [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]Goliath[/words] models:
1. remove entire [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]BM[/words] valve assembly so you're left with a
cylinder w/a [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]gaiter[/words] and a hole at the top
2. take the VV stopper and put it in the top of The [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]BM[/words] where the valve used to be.
3. wedge a small rubber washer or similar to create enough compression to keep the VV stopper in-place
4. fill your [words=https://officialhydromaxpump.com/?uid=6&oid=2&affid=98]BM[/words] w/water and mount it just like normal, once semi-secure you can use the hand pump to the desired pressure