Trackday - Helmet recommendations unusually large head

[Onager76]

Hi,
I am a new member and apologize if this is a rookie question or posted in the wrong spot.

I need an auto racing helmet for an upcoming track day, but my I have a big head. Not an apples to apples comparison, but my current motorcycles helmet is a 4xl. Does anyone have a recommendation for an auto helmet in 3xl/4xl size?

I have found two Bell helmets Bell (Racer Series) M.8 Auto Racing Helmet SA2015 and Bell - Sport Mag SA2015 Open Face Racing Helmet that go up to 4x. Would either of those be sufficient for trackdays at the ring?

Thank you

[Onager76]

Thank you for the replies. Sounds like I'll stick with the mc helmet for now. It will save some $ and i wont have to try to find something that fits