One of these will get it done in 27 hours or less:
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Or one of these twin cylinder bad boys would be a little faster:
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Another vote for a Viair inflator. Just looking at getting one and not sure which model or accessories to use though and if a cylinder is needed. I'd rather get a quality one with a good reputation that won't let you down when really needed.
I brought my 120 volt pancake compressor with us on the 3 week trip we're just on. Not a good idea to use it early in the morning and wake the CG up though. I had to air up all the tires a bit due to temp. and elevation change early one morning and fortunately had enough air in the tank to do the job.
Found out recently that the you sure can't expect to air up your tires at a gas station as the pumps aren't good for over 50 psi not to mention the ton of quarters you'd need.