Yes, you should inform your car insurance company about aftermarket performance parts and yes, it could affect your car insurance rates.
Most all automobile insurance companies require that performance parts be listed on your car insurance policy as some parts you place on your vehicle may make the risk unacceptable for the policy purchased and thus invalid. For this reason you should definitely notify your car insurance company to make certain you have the coverage you need.
If the performance or custom aftermarket parts are acceptable, there will most likely be an additional charge to have the parts covered in the event of a claim, otherwise the stock parts are what will be considered for a loss. Typically car insurance companies will add an endorsement to your policy to cover your non-factory parts. Sometimes this is referred to as an additional equipment endorsement or custom parts coverage.
If you want to install performance parts on your vehicle we advise you discuss the changes with your auto insurance provider first to make sure it is considered an acceptable part per their guidelines. If you fail to inform your car insurance company about performance parts it could void out your policy if they are unacceptable to the insurance company.
If the aftermarket parts are acceptable but they were not listed on your policy or given coverage through an endorsement and you were in an accident, the insurance company would only cover stock parts; your performance parts would not be replaced or given a monetary value.
Our partner Progressive offers coverage for custom parts and defines it as equipment that is not offered by the original manufacturer of the car or installed by the dealer as a part of the original sale.
If your current automobile insurance company does not cover the performance parts you want to use or you just want to shop for cheap car insurance, CarInsurance.com can help you out. We offer the ability to shop for car insurance online and the ability to purchase your policy directly through CarInsurance.com, so get started now with instant car insurance quotes.