I would like to put octane booster in my car. The car uses premium unleaded gas. Could I use regular gas and put octane booster without causing any damages? Thank you in advance.
I would not recommend adding octane booster to regular gasoline to try to make premium. The octane booster has various effectiveness and may or may not improve the octane from 87 to 91+.
Octane booster is usually used in high performance vehicles that require a higher octane fuel than even premium can provide. The octane booster will also not be cheaper in the long run than just running premium in the first place. With modern vehicles they are able to run with a lower octane fuel but they do this at the cost of engine performance, peak horsepower / torque, and the gas mileage worsens as the ECU must pull engine timing to accommodate the 87 octane gas.