Put the car on blocks if at all possible. Modern tires do develop flat spots
that usually work themselves out. Put rubber preservative on the side walls
to help prevent rubber dry rot and cracking.
Fill the tires to the normal pressure plus ~ 10-15% ~30-36 psi for most
14-15 inch Miata tires. Be sure to check the pressure before driving.
It's also a good idea to at least change the coolant and oil before storage.

There is an argument in favor of running the engine and driving the car
periodically instead of just storing it for a long period.

A trick often used with marine engines is to spray non gumming oil into the
intake (past the MAF, not before) until the engine quits.
(The plugs are usually replaced or cleaned before restarting for the first
time after storaage.)

"Diane" > wrote in message
...
> I just read that modern tires do not risk flat spots, hence should not
> overinflate for storage. Any opinions?
>
> -Phil (not Diane)
>
>