compression test help
 

ok i am looking at buying a 1980 rx-7 with 58000 km (canadian car) and the compression test shows 180psi for both rotors so my question is how dose this fit into this information

110+psi = Brand new engine in perfect condition.
100psi = great condition
90psi = avg
80psi = on it's last leg
70psi = you ain't getting anything out of this one.

so is this motor good or bad


and also the car is selling for 500 bucks and the body has only minor rust so if the motor is good is this car worth it