baiscally im trying to figure out how many seconds are between each fire of one of the 6 pistons in the car if the engine rpm is around 700rpm idle?

each cylinder fires every 2 rotations of the crank, regardless to the number of cylinders in the engine. 700 RPM /2 = 350 fires per minute per cylinder, or 5.8 fires per second per cylinder

or the much shorter answer: 0.17 seconds