Can I use my custom car online? August 15, 2019 18:12 Updated Follow https://support.nascarheat.com/customer/portal/articles/2872909-can-i-use-my-custom-car-online-?b_id=16861 Yes. Custom cars can be used online. Related articles How do I change my online car setup in NASCAR Heat 4? How do I get the SMI ticket offer? What if I want to exit the race and start again?