87 octane is the lowest grade of gas you can get in California. Your car should run fine burning it. The higher grade gasolines are meant for cars with higher compression ratios, basically meaning the piston compresses more air and fuel under higher pressure before it is ignited. Cars with higher compression ratios need to have higher octane fuel to prevent the pressure inside the combustion chamber from igniting the fuel and air before the spark plug is ignited by the distributor or the computer on modern cars. Higher octane fuel can withstand the higher pressures inside high performance engines with higher compression ratios without detonating prematurely.