I went and played around at the dunes yesterday and today. Car is a 99 Outback wagon, EJ25D, 4EAT. Original suspension, stock size (205/70-15) all seasons (Toyo Extensa A/S). Pretty much the only mods are tube front bumper/no rear bumper skin, and a WRX seat. I was running 15f/13r. There was a nice bulge, but not excessive. It was doing quite well, I was pretty surprised at how capable it was. 

 

After one landing the steering felt a little funny, so I stopped and found the front right tire was flat. It didn't appear to be off the bead, but had zero air in it. A little CO2 from a friend's tank and it filled back up no problem, I went to 15psi again. I didn't play around after that, just went back to camp and then home. 

 

Was I running excessively low pressures? I generally hear half of street pressure is about right, which was dead on up front. The rears were a little lower but you're less likely to pop a bead on them. 

 

What pressures do you run?

15 is about right

 

But you have to be prepared to check and fill often.

 

Sand works in under the bead and begins to let the air seep out slowly.

 

Check every hour or 2.

None of the other 3 appeared to lose any air, and the one that went flat held the same pressure for the next 16 hours. I don't think I was playing for a full hour before it went flat, either. 

Here's some of the stuff I did out there

 

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