If you’re increasing the value of your car with modifications, then claims you make may be higher, as it tends to be more expensive to repair or replace parts.
There’s also the potential increased risk of making a claim. You may have made your car faster, and so could be more likely to be in a speed related accident.
Your gorgeous machine may also be at greater risk of theft, particularly if you’ve had expensive tech installed, or you’ve modified its performance to make it turbo powered.
Insurers could also assume that any additional work done to the mechanics or structure from the original spec cannot be guaranteed and may affect the car’s integrity.
Also, if you are a young driver and want to transform your little run-around into a beast we’re afraid there is a higher chance your premiums will increase more dramatically. Statistically, this is because young drivers are more likely to claim on their car insurance.