So I've got an '80 RX-7 with a full tank of 7 year old gas, I'm wanting to restore the car and get it running. What now?

 

Drain that old gas and put new in. Unhook the line going to the carb and turn the fuel pump on. Let it pump the gas into a container. If its an 83-85, your going to have to hot wire the pump or find another way to drain the gas as the fuel pump doesn't come on unless your cranking the engine. Earlier cars have it so the fuel pump comes on when the key is in the run possition without the engine running.

 

I know my car is a later one than the original post, but I have an 84 GSL (NOT gsl-se) and it has an electric fuel pump (stock)

Just FYI

 

pull the plug on the bottom of the tank, that gas will be very rotten.

 

The 80 doesn't have a plug. have to drain it through the fuel line or remove tank.

 

Pumping it like 85rotarypower said is a good idea and would work the fastest, but it might be a good idea to simply drop your tank and see how rusty it is in the inside. There's no point in jumping the gun in getting it started if your going to pump a buncha rusty varnishy shoddy gas through your pump, fuel filter, and lines. You say want to restore it, so why add the headache. I say drop your tank and manually dump it out, that way you can assess your tank. These rotary tanks seem to rust out fairly often.